# Technical Sciences Grade 12 P2 Gauteng Mock 2018 QP

> Grade 12 Technical Sciences Paper 2 question paper from the Gauteng Mock Exam 2018, 19 pages. Read online or download the free PDF.

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- Updated: 2026-09-27
- Subject: Technical Sciences
- Grade: Grade 12
- Document type: Question paper
- Year: 2018
- Exam period: Gauteng Mock Exam
- Paper: 2
- Curriculum: CAPS
- Pages: 19

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### Page 1

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            GAUTENG DEPARTMENT OF EDUCATION
                   PREPARATORY EXAMINATION
                                 2018
                                  11102

                           TECHNICAL SCIENCES

                                PAPER 2

TIME:    3 hours

MARKS: 150

15 pages + 4 data sheets

                                                P.T.O.

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                                         TECHNICAL SCIENCES P1                  2
                                                             11102 / 18

INSTRUCTIONS AND INFORMATION

1.    This question paper consists of NINE questions. Answer ALL the questions in
      the ANSWER BOOK.

2.    Start EACH question on a NEW page in the ANSWER BOOK.

3.    Number the answers correctly according to the numbering system used in this
      question paper.

4.    Leave ONE line between two sub-questions, for example, between
      QUESTION 2.1 and QUESTION 2.2.

5.    You may use a non-programmable calculator.

6.    You may use appropriate mathematical instruments.

7.    You are advised to use the attached DATA SHEETS.

8.    Show ALL formulae and substitutions in ALL calculations.

9.    Round-off your final numerical answers to a minimum of TWO decimal places.

10.   Give brief motivations, discussions etc. where required.

11.   Write neatly and legibly.

                                                                              P.T.O.

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                                             TECHNICAL SCIENCES P1                        3
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QUESTION 1: MULTIPLE-CHOICE QUESTIONS

Four options are provided as possible answers to the following questions.
Each question has only ONE correct answer. Choose the correct answer and
write only the letter (A – D) next to the question number (1.1 – 1.10) in the
ANSWER BOOK, e.g. 1.11 D.

1.1    Which of the following are structural isomers?

             1                               2                               3
             CH3                                 CH2   CH3
                                                                       CH2         CH2
      H3C    C      CH3           H3C   HC                       H3C         CH2          CH3

             CH3                                 CH3

 A     Only 1 and 2

 B     Only 2 and 3

 C     Only 1 and 3

 D     1, 2 and 3                                                                                 (2)

1.2    Which ONE of the IUPAC names below is CORRECT for the given structure?

                                                       H

                          H   H     H        H         C     H    H    H

                   H      C   C     C                  C          C    C      H

                          H   H     H        H         C     H    Cl   H

                                                       H

  A     4-dimethyl-5-chlorohexane

  B    3,3-dimethyl-2-chlorohexane

  C     2-methyl-3,3-chlorohexane

  D    2-chloro-3,3-dimethylhexane                                                                (2)

                                                                                         P.T.O.

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                                                    TECHNICAL SCIENCES P1              4
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1.3   Which ONE of the following cannot be an ester or a carboxylic acid?

      A      C3H6O

      B      C3H6O2

      C      CH2O2

      D      C2H4O2                                                                            (2)

1.4   Which monomer is used to produce polythene?

      A      Chloroethene

      B      Propene

      C      Benzene

      D      Ethene                                                                            (2)

1.5   A certain standard, electrochemical cell can be presented as follows:

      Pt , I- / I2 // Fe3+ / Fe2+ , Pt

      Which ONE of the following will serve as the reducing agent?

      A      I-

      B      I2

      C      Fe3+

      D      Fe2+                                                                              (2)

1.6   In an electrochemical cell, what relationship must be TRUE about the values
      of Eөoxidising agent and Eөreducing agent for the reaction to occur spontaneously
      under standard conditions?

      A      Eөreducing agent > 0 and Eөoxidising agent > 0

      B      Eөreducing agent < 0 and Eөoxidising agent < 0

      C      Eөreducing agent > Eөoxidising agent

      D      Eөreducing agent < 0 and Eөoxidising agent > 0                                    (2)

                                                                                      P.T.O.

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                                             TECHNICAL SCIENCES P1                   5
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1.7    When a ray of light moves from an optically more dense medium to an
       optically less dense medium, then the …

       A    wavelength and the speed of the light will increase.

       B    wavelength of the light will decrease, but the speed of the light will
            increase.

       C    frequency and speed of the light will decrease.

       D    wavelength, frequency and speed of the light will increase.                      (2)

1.8    Which ONE of the following is NOT true regarding EM rays?

       A    Can be reflected

       B    Can undergo interference

       C    Can undergo refraction

       D    Is a longitudinal wave                                                           (2)

1.9    A ray of light hits the surface between water and air at a right angle. Which
       ONE of the following statements is correct?

       A    The angle of incidence is 90˚.

       B    Total internal reflection occurs.

       C    The frequency of the ray of light remains constant.

       D    The angle of incidence is equal to the critical angle.                           (2)

1.10   Which ONE of the following uses does not fit with the type of electromagnetic
       wave?

       A    Micro wave – Television broadcasts

       B    Gamma rays – Cancer radiation

       C    Infrared – Heating of food

       D    Ultraviolet light – Sterilisation of food                                        (2)
                                                                                             [20]

                                                                                    P.T.O.

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                                              TECHNICAL SCIENCES P1                                6
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QUESTION 2 (Start on a new page.)

Consider the representation of organic molecules A to F below.

      A                     H H                    B                             H
                                                                     H
                        H C C H                                                  C        H
                                                                         C            C
                            H H                                  H
                                                                             H        H

      C                 H   Br   H    H            D   Ethyl ethanoate
                  H     C   C    C    C   H

                        H   Br   Br   H

      E   Propan-1-ol                              F                     H

                                                                 H       C            H

                                                           H     H                    H       H        O
                                                       H   C     C       C            C       C    C

                                                           H     H       H            H       H        H

2.1       Define a homologous series.                                                                      (2)

2.2       Write down the NAME of the homologous series to which EACH of the
          following compounds belong:

          2.2.1   B                                                                                        (1)

          2.2.2   D                                                                                        (1)

          2.2.3   E                                                                                        (1)

          2.2.4   F                                                                                        (1)

                                                                                                  P.T.O.

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                                        TECHNICAL SCIENCES P1                    7
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2.3   Write down the letter that represents a compound that:

      2.3.1    Is a saturated hydrocarbon                                                (1)

      2.3.2    Is a halo alkane                                                          (1)

      2.3.3    Has a general formula CnH2n+1OH                                           (1)

2.4   Write down the:

      2.4.1    Molecular formula of the next compound in the same homologous
               series as compound B                                                      (2)

      2.4.2    Structural formula of compound E                                          (3)

      2.4.3    IUPAC name of compound B                                                  (3)

      2.4.4    Structural formula of the functional group of compound D                  (2)
                                                                                         [19]

                                                                                P.T.O.

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                                                 TECHNICAL SCIENCES P1                         8
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QUESTION 3 (Start on a new page.)

3.1    The earliest known work with polymers was the rubber industry in
       pre-Columbian Mexico. The Mesoamericans knew how to combine latex of
       the rubber tree with the juice of the morning glory plant in different proportions
       to get rubber with different properties for different products, such as bouncing
       balls, sandals, and rubber bands. Polymers are large molecules composed of
       smaller monomer units.

       3.1.1     Define a monomer.                                                                     (2)

       3.1.2     Identify and draw the recurring monomer in the following polymer.                     (1)

                          H    H   Cl   H   H     H   Cl   H   Cl   H

                     H    C    C   C    C   C     C   C    C   C    C   H

                          Cl   H   H    H   Cl    H   H    H   H    H

       3.1.3     Polythene is the most common plastic. The annual global production is
                 around 80 million tonnes.

                   (a)    Name TWO properties of polythene which makes it useful.                      (2)

                    (b)   Name TWO uses of polythene.                                                  (2)

3.2    Consider the table below and answer the questions that follow.

                 SYSTEMATIC                                         BOILING POINT
                                            FORMULA
                    NAME                                                 (˚C)

               Chloromethane                     CH3Cℓ                      -24,1
               Dichloromethane                   CH2Cℓ2                     40,1
               Trichloromethane                  CHCℓ3                      61,8
               Tetrachloromethane                 CCℓ4                      76,6

       3.2.1     Name the intermolecular forces in alkyl halides                                       (1)

       3.2.2     Describe the relationship between the number of chlorine atoms and
                 boiling points as presented in the above table.                                       (2)

       3.2.3     Write down the formula of the alkyl halide that is dangerous at 25˚C.                 (1)

       3.2.4     Provide a reason for your answer to Question 3.2.3.                                   (2)
                                                                                                       [13]

                                                                                              P.T.O.

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                                            TECHNICAL SCIENCES P1                      9
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QUESTION 4 (Start on a new page.)

Fossil fuel is a general term for buried combustible geologic deposits of organic
materials. These deposits are formed from decayed plants and animals that have been
converted to crude oil, coal, natural gas, or heavy oils by exposure to heat and
pressure in the earth's crust over hundreds of millions of years. Alkanes are the most
important of fossil fuels. Some countries like Canada produce 18.3 billion cubic feet of
natural gas per day. Propane is produced as a by-product of two other processes,
natural gas processing and petroleum refining. Propane is a cleaner-burning
alternative fuel. Butane is another gaseous fuel derived from petroleum.

4.1      Write a balanced equation to show the complete combustion reaction of
         butane in excess oxygen.                                                              (3)

4.2      But-2-ene can be converted to other compounds by means of different
         organic reactions represented by F, G, H and I, as shown below.

                                                   F              Butan-2-ol
                            But-2-ene

                               G                                        I
                                                  H
                              Butane                              2-Bromobutane
                                                  Br2

         Write down the TYPE of the reaction represented by:

         4.2.1    F                                                                            (2)

         4.2.2    G                                                                            (2)

         4.2.3    H                                                                            (2)

         During reaction I, the alkyl halide (haloalkane) reacts in the presence of a
         base to form an alcohol.

         4.2.4    Give the NAME of a suitable base used.                                       (1)

         4.2.5    Name TWO reaction conditions that are required.                              (2)
                                                                                               [12]

                                                                                      P.T.O.

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                                              TECHNICAL SCIENCES P1                    10
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QUESTION 5 (Start on a new page.)

Steel ships needs to be protected from corrosion. One method of protecting ships is by
means of the Sacrificial anode system. Sacrificial anodes or metals have been used
since 1824. Zinc is popularly used as a sacrificial metal.

5.1     What is the purpose of attaching the zinc bars to the hulls of steel ships?            (1)

5.2     Use the Table of Standard Reduction Potentials to explain the answer to
        Question 5.1.                                                                          (2)

5.3     A magnesium rod is placed in an iron (II) chloride solution. Write down the
        following:

        5.3.1     The chemical equation                                                        (1)

        5.3.2     The oxidation half-reaction                                                  (2)

        5.3.3     The reduction half-reaction                                                  (2)

        5.3.4     The balanced net reaction                                                    (2)

                                                                                      P.T.O.

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                                                TECHNICAL SCIENCES P1                 11
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5.4     Electrolytic cells are commonly used in the process of electroplating.
        Electroplating involves passing an electric current through a solution called an
        electrolyte. Silver plating is shown in the diagram below.

      Silver electrode                                   Steel electrode

           Electrolyte

        5.4.1    Define an electrolytic cell.                                                 (2)

        5.4.2    Which electrode will act as the anode? (Write only SILVER or
                 STEEL.)                                                                      (1)

        5.4.3    Which reaction occurs at the cathode?                                        (1)

        5.4.4    Write down the half-reaction that occurs at the anode.                       (2)

        5.4.5    Which solution can be used as an electrolyte?                                (1)
                                                                                              [17]

                                                                                     P.T.O.

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                                            TECHNICAL SCIENCES P1                       12
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QUESTION 6 (Start on a new page.)

6.1    A learner constructed an electrochemical cell using silver and zinc electrodes.
       The cell was set up as illustrated below.

                                                    V
                                                 Salt bridge

                          Ag electrode                           Zn electrode

                                  Ag+                            Zn2+ (aq)
                                  (zzzaq)

       6.1.1     Identify the type of electrochemical cell shown in the diagram above.          (1)

       6.1.2     Which energy conversion occurs in this type of cell?                           (2)

       6.1.3     Describe the movement of the ions in the solutions.                            (2)

       6.1.4     Write down TWO functions of the salt bridge.                                   (2)

       6.1.5     What is the direction of electron flow in the external circuit?                (2)

       6.1.6     Why is KNO3 the preferred electrolyte to be used in the salt bridge,
                 instead of BaCl2?                                                              (2)

6.2    For this cell:

       6.2.1     Write down the net reaction.                                                   (2)

       6.2.2     Give the standard conditions.                                                  (2)

       6.2.3     Write down the cell notation.                                                  (3)

       6.2.4     Use the Table of Standard Reduction Potentials to calculate the emf.           (2)
                                                                                                [20]

                                                                                       P.T.O.

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                                              TECHNICAL SCIENCES P1                   13
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QUESTION 7 (Start on a new page.)

The following ray diagram shows reflection on a flat plane.

                               A                       B
                                         C

                                         1 2
                                   20°

7.1      Write down the laws of reflection.                                                   (2)

7.2      Give suitable NAMES for lines A, B and C.                                            (3)

7.3      Write down the NAME and the MAGNITUDE of the following:

         7.3.1    Angle 1                                                                     (2)

         7.3.2    Angle 2                                                                     (2)

7.4      When white light falls onto a triangular prism, the following phenomenon is
         observed.

         7.4.1    What do we call this phenomenon?                                            (1)

         7.4.2    Write a definition for the phenomenon named in Question 7.5.1.              (2)

         7.4.3    Which colour of light is refracted the least?                               (1)

         7.4.4    Explain the answer to Question 7.4.3 in terms of the wavelength.            (2)
                                                                                              [15]

                                                                                     P.T.O.

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                                              TECHNICAL SCIENCES P1                       14
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QUESTION 8 (Start on a new page.)

Light moves from medium 1 to medium 2 to medium 3. The diagram below illustrates
the path of a ray of light through the different media.

      Medium 1

      Medium 2

      Medium 3
8.1     Define refraction.                                                                        (2)

8.2     Identify the phenomenon taking place between medium 2 and medium 3.                       (1)

8.3     The media in the diagram above have different optical densities.

        8.3.1     Which medium is optically denser, medium 1 or medium 2?                         (1)

        8.3.2     Explain the answer to Question 8.3.1.                                           (2)

8.4     8.4.1     In which medium, 1, 2 or 3, is the angle of incidence larger than the
                  critical angle?                                                                 (1)

        8.4.2     Justify the answer to Question 8.4.1.                                           (2)

8.5     How does the optical density between medium 2 and medium 3 compare?                       (1)

8.6     Name TWO:

        8.6.1     Conditions for total internal reflection                                        (2)

        8.6.2     Applications of total internal reflection                                       (2)

8.7     Short-sighted people cannot see faraway objects because their eyeballs are
        too long. This results in light from distant objects falling in front of the retina,
        thus making the image blurred. To correct this defect, optometrists prescribe
        lenses that enable patients to see distant objects.

        Use a labelled diagram to illustrate how such a lens will correct short-
        sightedness.                                                                              (5)
                                                                                                  [19]
                                                                                         P.T.O.

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                                              TECHNICAL SCIENCES P2                          15
                                                                                 09 / 18

QUESTION 9 (Start on a new page.)

In physics, electromagnetic radiation refers to the waves of the electromagnetic field,
propagating through space-time, carrying electromagnetic radiant energy.

9.1      Define an electromagnetic wave.                                                            (2)

9.2      The diagram below represents radiations of the electromagnetic spectrum.

         Infrared    Radio                             Gamma       Ultraviolet
                               X-rays    Microwaves                                 Visible light
                     waves                              rays          rays

         9.2.1      Arrange the spectrum in order of decreasing wavelength.                         (2)

         9.2.2      In which radiation will a photon have the lowest energy?                        (1)

         9.2.3      Explain the answer to Question 9.2.2.                                           (2)

9.3      Calculate the energy of a photon of an electromagnetic wave with a
         wavelength of 520 pm.                                                                      (5)

9.4      How will the energy of a photon with a wavelength of 350 pm compare with
         that calculated in Question 9.3? (Write only GREATER THAN, SMALLER
         THAN or EQUAL TO).                                                                         (1)

9.5      Identify the electromagnetic radiation best suited for use in the following:

         9.5.1      Security scanners                                                               (1)

         9.5.2      Sterilisation of food and appliances                                            (1)
                                                                                                    [15]

                                                                                     TOTAL:         150

                                              END

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                                                        TECHNICAL SCIENCES P2                                     16
                                                                                                   09 / 18

                      DATA FOR TECHNICAL SCIENCES GRADE 12
                                    PAPER 2

                GEGEWENS VIR TEGNIESE WETENSKAPPE GRAAD 12
                                VRAESTEL 2

TABLE 1/TABEL 1

PHYSICAL CONSTANTS/FISIESE KONSTANTES
     CONSTANT/KONSTANTE       SYMBOL/SIMBOOL                                               VALUE/WAARDE
Planck's constant                                                                                         -34
Planck se konstante                  h                                                        6,63 x 10         J.s
Speed of light                                                                                        8
Spoed van lig                        c                                                         3 x 10 m.s-1

TABLE 2/TABEL 2

WAVES, SOUND AND LIGHT/GOLWE, KLANK EN LIG
Speed/Spoed                                               c=fλ
Energy/Energie                                            E = hf

                                                          or/of

                                                                hc
                                                          E=
                                                                 λ

TABLE 3/TABEL 3

ELECTROCHEMISTRY/ELEKTROCHEMIE
Emf/Emk       Eθcell = Eθcathode − Eθanode / E θsel = E katode
                                                        θ
                                                               − E θanode

                       or/of

                       E θcell = E reduction
                                   θ
                                             − E θoxidation / E θsel = E reduksie
                                                                         θ
                                                                                  − E θoksidasie

                       or/of

                       E θcell = E oxidising
                                   θ                   θ
                                             agent − E reducing agent / E sel = E oksideermiddel − E reduseermiddel
                                                                          θ       θ                  θ

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                                                                                             TECHNICAL SCIENCES P2                                                                         17
                                                                                                                            09 / 18

                                                             TABLE 4A: STANDARD REDUCTION POTENTIALS
                                                             TABEL 4A: STANDAARD-REDUKSIEPOTENSIALE

                                                                                                                   θ
                                                                      Half-reactions/Halfreaksies                  E (V)
                                                                         F2(g) + 2e−         ⇌   2F−               + 2,87
                                                                           Co + e−
                                                                                                   2+
                                                                             3+
                                                                                             ⇌   Co                + 1,81
                                                                    H2O2 + 2H +2e−           ⇌
                                                                              +
                                                                                                 2H2O              +1,77
                                                                       −
                                                                  MnO 4 + 8H + 5e−
                                                                                                   2+
                                                                                +
                                                                                             ⇌   Mn       + 4H2O   + 1,51
                                                                                     −                −
                                                                           Cℓ2(g) + 2e       ⇌   2Cℓ               + 1,36
                                                                     2−
                                                                Cr2O 7 + 14H + 6e−
                                                                                                     3+
                                                                            +
                                                                                             ⇌   2Cr + 7H2O        + 1,33
                                                                   O2(g) + 4H + 4e−          ⇌
                                                                                +
                                                                                                 2H2O              + 1,23
                                                                   MnO2 + 4H + 2e−
                                                                                                     2+
                                                                              +
                                                                                             ⇌   Mn + 2H2O         + 1,23
                                                                           Pt + 2e−          ⇌
                                                                             2+
                                                                                                 Pt                + 1,20
                                                                         Br2(ℓ) + 2e−        ⇌   2Br−              + 1,07
                                                                   NO 3 + 4H + 3e−
                                                                       −      +
                                                                                             ⇌

Increasing oxidising ability/Toenemende oksiderende vermoë
                                                                                                 NO(g) + 2H2O      + 0,96

                                                                                                                               Increasing reducing ability/Toenemende reduserende vermoë
                                                                         Hg + 2e−            ⇌   Hg(ℓ)
                                                                               2+
                                                                                                                   + 0,85
                                                                           Ag + e−           ⇌
                                                                             +
                                                                                                 Ag                + 0,80
                                                                    NO 3 + 2H + e−
                                                                       −     +
                                                                                             ⇌   NO2(g) + H2O      + 0,80
                                                                            Fe + e−
                                                                                                    2+
                                                                                3+
                                                                                             ⇌   Fe                + 0,77
                                                                   O2(g) + 2H + 2e−          ⇌
                                                                              +
                                                                                                 H2O2              + 0,68
                                                                             I2 + 2e−        ⇌   2I−               + 0,54
                                                                            Cu + e−          ⇌
                                                                                +
                                                                                                 Cu                + 0,52
                                                                    SO2 + 4H + 4e−           ⇌
                                                                              +
                                                                                                 S + 2H2O          + 0,45
                                                                    2H2O + O2 + 4e−          ⇌   4OH−              + 0,40
                                                                          Cu + 2e−           ⇌
                                                                             2+
                                                                                                 Cu                + 0,34
                                                                      2−
                                                                  SO 4 + 4H + 2e−            ⇌
                                                                                +
                                                                                                 SO2(g) + 2H2O     + 0,17
                                                                                         −         +
                                                                                2+
                                                                           Cu + e            ⇌   Cu                + 0,16
                                                                          Sn + 2e−
                                                                                                    2+
                                                                             4+
                                                                                             ⇌   Sn                + 0,15
                                                                       S + 2H + 2e−          ⇌
                                                                              +
                                                                                                 H2S(g)            + 0,14
                                                                           2H + 2e−          ⇌
                                                                              +
                                                                                                 H2(g)              0,00
                                                                          Fe + 3e−           ⇌                     − 0,06
                                                                             3+
                                                                                                 Fe
                                                                          Pb + 2e−           ⇌                     − 0,13
                                                                             2+
                                                                                                 Pb
                                                                          Sn + 2e−           ⇌                     − 0,14
                                                                             2+
                                                                                                 Sn
                                                                           Ni + 2e−          ⇌                     − 0,27
                                                                             2+
                                                                                                 Ni
                                                                          Co + 2e−           ⇌                     − 0,28
                                                                             2+
                                                                                                 Co
                                                                          Cd + 2e−           ⇌                     − 0,40
                                                                             2+
                                                                                                 Cd
                                                                            Cr + e−
                                                                                                    2+
                                                                                             ⇌                     − 0,41
                                                                               3+
                                                                                                 Cr
                                                                          Fe + 2e−           ⇌                     − 0,44
                                                                             2+
                                                                                                 Fe
                                                                          Cr + 3e−           ⇌                     − 0,74
                                                                             3+
                                                                                                 Cr
                                                                          Zn + 2e−           ⇌                     − 0,76
                                                                             2+
                                                                                                 Zn
                                                                         2H2O + 2e−          ⇌   H2(g) + 2OH−      − 0,83
                                                                          Cr + 2e−           ⇌                     − 0,91
                                                                             2+
                                                                                                 Cr
                                                                          Mn + 2e−           ⇌                     − 1,18
                                                                             2+
                                                                                                 Mn
                                                                           Aℓ + 3e−          ⇌   Aℓ                − 1,66
                                                                             3+

                                                                          Mg + 2e−           ⇌                     − 2,36
                                                                             2+
                                                                                                 Mg
                                                                            Na + e−          ⇌                     − 2,71
                                                                                +
                                                                                                 Na
                                                                          Ca + 2e−           ⇌                     − 2,87
                                                                             2+
                                                                                                 Ca
                                                                           Sr + 2e−          ⇌                     − 2,89
                                                                             2+
                                                                                                 Sr
                                                                          Ba + 2e−           ⇌                     − 2,90
                                                                             2+
                                                                                                 Ba
                                                                                +  -
                                                                             Cs + e          ⇌   Cs                - 2,92
                                                                                   −
                                                                                             ⇌                     − 2,93
                                                                                +
                                                                              K +e               K
                                                                             Li + e−         ⇌                     − 3,05
                                                                                +
                                                                                                 Li

### Page 18

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                                                                                            TECHNICAL SCIENCES P2                                                                         18
                                                                                                                             09 / 18

                                                             TABLE 4B: STANDARD REDUCTION POTENTIALS
                                                             TABEL 4B: STANDAARD-REDUKSIEPOTENSIALE
                                                                                                                    θ
                                                                      Half-reactions/Halfreaksies                   E (V)
                                                                               Li + e−      ⇌                       − 3,05
                                                                                    +
                                                                                                Li
                                                                                K + e−      ⇌                       − 2,93
                                                                                  +
                                                                                                K
                                                                              Cs + e−       ⇌                       − 2,92
                                                                                 +
                                                                                                Cs
                                                                            Ba + 2e−        ⇌                       − 2,90
                                                                               2+
                                                                                                Ba
                                                                             Sr + 2e−       ⇌                       − 2,89
                                                                               2+
                                                                                                Sr
                                                                            Ca + 2e−        ⇌                       − 2,87
                                                                               2+
                                                                                                Ca
                                                                              Na + e−       ⇌                       − 2,71
                                                                                  +
                                                                                                Na
                                                                            Mg + 2e−        ⇌                       − 2,36
                                                                               2+
                                                                                                Mg
                                                                             Aℓ + 3e−       ⇌   Aℓ                  − 1,66
                                                                               3+

                                                                            Mn + 2e−        ⇌                       − 1,18
                                                                               2+
                                                                                                Mn
                                                                            Cr + 2e−        ⇌                       − 0,91
                                                                               2+
                                                                                                Cr
                                                                           2H2O + 2e−       ⇌   H2(g) + 2OH−        − 0,83
                                                                            Zn + 2e−        ⇌                       − 0,76
                                                                               2+
                                                                                                Zn
                                                                            Cr + 3e−        ⇌                       − 0,74
                                                                               3+
                                                                                                Cr

Increasing oxidising ability/Toenemende oksiderende vermoë
                                                                            Fe + 2e−        ⇌                       − 0,44
                                                                               2+
                                                                                                Fe
                                                                              Cr + e−
                                                                                                   2+
                                                                                            ⇌                       − 0,41
                                                                                 3+
                                                                                                Cr

                                                                                                                              Increasing reducing ability/Toenemende reduserende vermoë
                                                                            Cd + 2e−        ⇌                       − 0,40
                                                                               2+
                                                                                                Cd
                                                                            Co + 2e−        ⇌                       − 0,28
                                                                               2+
                                                                                                Co
                                                                             Ni + 2e−       ⇌                       − 0,27
                                                                               2+
                                                                                                Ni
                                                                            Sn + 2e−        ⇌                       − 0,14
                                                                               2+
                                                                                                Sn
                                                                            Pb + 2e−        ⇌                       − 0,13
                                                                               2+
                                                                                                Pb
                                                                            Fe + 3e−        ⇌                       − 0,06
                                                                               3+
                                                                                                Fe
                                                                             2H + 2e−
                                                                                +
                                                                                            ⇌   H2(g)                0,00
                                                                         S + 2H + 2e−       ⇌
                                                                                +
                                                                                                H2S(g)              + 0,14
                                                                            Sn + 2e−
                                                                                                   2+
                                                                               4+
                                                                                            ⇌   Sn                  + 0,15
                                                                             Cu + e−
                                                                                                    +
                                                                                 2+
                                                                                            ⇌   Cu                  + 0,16
                                                                      2−
                                                                  SO 4 + 4H + 2e−           ⇌
                                                                                +
                                                                                                SO2(g) + 2H2O       + 0,17
                                                                                        −
                                                                               2+
                                                                          Cu + 2e           ⇌   Cu                  + 0,34
                                                                    2H2O + O2 + 4e−         ⇌   4OH−                + 0,40
                                                                    SO2 + 4H + 4e−          ⇌
                                                                              +
                                                                                                S + 2H2O            + 0,45
                                                                            Cu + e−         ⇌
                                                                                +
                                                                                                Cu                  + 0,52
                                                                             I2 + 2e−       ⇌   2I−                 + 0,54
                                                                   O2(g) + 2H + 2e−         ⇌
                                                                              +
                                                                                                H2O2                + 0,68
                                                                            Fe + e−
                                                                                                   2+
                                                                               3+
                                                                                            ⇌   Fe                  + 0,77
                                                                    NO 3 + 2H + e−
                                                                        −       +
                                                                                            ⇌   NO2(g) + H2O        + 0,80
                                                                            Ag + e−         ⇌
                                                                                    +
                                                                                                Ag                  + 0,80
                                                                          Hg + 2e−          ⇌   Hg(ℓ)
                                                                             2+
                                                                                                                    + 0,85
                                                                   NO 3− + 4H + 3e−
                                                                              +
                                                                                            ⇌   NO(g) + 2H2O        + 0,96
                                                                         Br2(ℓ) + 2e−       ⇌   2Br−                + 1,07
                                                                          Pt + 2 e−         ⇌
                                                                            2+
                                                                                                Pt                  + 1,20
                                                                   MnO2 + 4H + 2e−
                                                                                                   2+
                                                                              +
                                                                                            ⇌   Mn + 2H2O           + 1,23
                                                                   O2(g) + 4H + 4e−         ⇌
                                                                              +
                                                                                                2H2O                + 1,23
                                                                    2−
                                                                Cr2O 7 + 14H + 6e−
                                                                                                      3+
                                                                                +
                                                                                            ⇌   2Cr        + 7H2O   + 1,33
                                                                                        −          −
                                                                           Cℓ2(g) + 2e      ⇌   2Cℓ                 + 1,36
                                                                      −
                                                                  MnO 4 + 8H + 5e−
                                                                                                  2+
                                                                            +
                                                                                            ⇌   Mn + 4H2O           + 1,51
                                                                   H2O2 + 2H +2 e−          ⇌
                                                                                +
                                                                                                2H2O                +1,77
                                                                          Co + e−
                                                                                                   2+
                                                                             3+
                                                                                            ⇌   Co                  + 1,81
                                                                         F2(g) + 2e−        ⇌   2F −
                                                                                                                    + 2,87

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