# Technical Sciences Grade 12 P2 NSC November 2019 QP (Eng)

> Grade 12 Technical Sciences Paper 2 question paper from the NSC November Exam 2019 (English), 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: 2019
- Exam period: NSC November Exam
- Paper: 2
- Curriculum: CAPS
- Pages: 19

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Technical Sciences · Grade 12 · NSC November Exam · 2019. Question paper, 19 pages. Read online or download the PDF.

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### Page 1

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                                NATIONAL
                           SENIOR CERTIFICATE

                                   GRADE 12

                           TECHNICAL SCIENCES P2

                                NOVEMBER 2019

MARKS: 150

TIME: 3 hours

              This question paper consists of 16 pages and 3 data sheets.

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Technical Sciences/P2                         2                       DBE/November 2019
                                             NSC

INSTRUCTIONS AND INFORMATION

1.        Write your centre number and examination number in the appropriate spaces
          on the ANSWER BOOK.

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

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

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

5.        Leave ONE line between two subquestions, e.g. between QUESTION 2.1 and
          QUESTION 2.2.

6.        You may use a non-programmable calculator.

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

8.        Round off your FINAL numerical answers to a minimum of TWO decimal
          places.

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

10.       Write neatly and legibly.

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Technical Sciences/P2                        3                          DBE/November 2019
                                            NSC

QUESTION 1: MULTIPLE-CHOICE QUESTIONS

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

1.1       Which ONE of the following organic molecules consists of single bonds only?

          A     Propene

          B     Propanol

          C     Propanoic acid

          D     Propylmethanoate                                                               (2)

1.2       Which ONE of the following organic molecules is used as fuels?

          A     Carboxylic acids

          B     Aldehydes

          C     Alkanes

          D     Esters                                                                         (2)

1.3       Consider the two structural formulae given below.

                                                              H   H    H
                                                      H       C   C    C H
                H       H    H   H
                                                              H    H
          H     C       C    C   C   H                         H C H
                H       H    H   H           and                 H

          The two structures represent … isomers.

          A     chain

          B     positional

          C     functional

          D     unsaturated                                                                    (2)

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Technical Sciences/P2                              4                      DBE/November 2019
                                                  NSC

1.4       Identify the product formed during the addition reaction of but-2-ene.

          A                                             B
                        H H          H
                                                                H   H     H        H
                H       C    C       C        H
                                                            H   C   C     C        C       H
                        H             H                         H   H     H        H
                        H C          H
                             H
          C                          H    H             D       H H     H H
                        H
                H       C   C        C    C       H         H   C C      C C           H
                            H        H    H                     H H        H
                                                                  H      C H
                                                                         H                       (2)

1.5       In which ONE of the following is chemical energy converted to electrical
          energy?

          A      Oxidation reaction

          B      Electrolytic cell

          C      Galvanic cell

          D      Electrolysis                                                                    (2)

1.6       What is the oxidation number of chlorine in CuC2?

          A      +2

          B      -2

          C      +1

          D      -1                                                                              (2)

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Technical Sciences/P2                            5                            DBE/November 2019
                                                NSC

1.7       Total internal reflection of light is possible if the angle of incidence is …

          A      equal to the critical angle.

          B      greater than the critical angle.

          C      equal to the angle of refraction.

          D      less than the angle of refraction.                                                  (2)

1.8       An object should be placed … to obtain an enlarged and inverted image on a
          screen when a convex lens is used.

          A      at F

          B      at 2F

          C      between F and 2F

          D      between the optical centre and F                                                    (2)

1.9       Which colour of white light is refracted the most during dispersion?

          A      Red

          B      Blue

          C      Green

          D      Violet                                                                              (2)

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                                            NSC

1.10      In the diagram below, a learner traced the path of a ray of light through a
          glass slab for DIFFERENT VALUES of the angle of incidence (𝑖) and
          measured the corresponding values of the angle of refraction (𝑟) and the
          angle of emergence (𝑒).

                                             𝑖

                                                 𝑟

                                                        𝑒

          What will be the relationship between 𝑖, 𝑟 and 𝑒?

          A      𝑖>𝑒>𝑟

          B      𝑖=𝑒>𝑟

          C      𝑖<𝑒<𝑟

          D      𝑖=𝑒<𝑟                                                                        (2)
                                                                                             [20]

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Technical Sciences/P2                         7                         DBE/November 2019
                                             NSC

QUESTION 2 (Start on a new page.)

Organic molecules are used in a variety of industries including food, pharmaceuticals,
fuels and construction. They include homologous series such as alkanes, alkenes,
alkynes, haloalkanes, alcohols, carboxylic acids, ketones, aldehydes and esters.

2.1       Define the term homologous series.                                                    (2)

2.2       Identify any ONE homologous series that is a hydrocarbon in the list above.           (1)

2.3       Hydrocarbons can either be saturated or unsaturated. Distinguish between
          saturated and unsaturated hydrocarbons.                                               (2)

The table below represents organic compounds with different functional groups.

                                                             H     H      H        OH
      A   Methyl ethanoate                         B
                                                       H     C     C      C        C      H
                                                             H     H      H        H

                     H   H   H     O                        H            H
      C                                            D
           H         C   C   C     C                        C     C      C     H
                                        H
                     H   H   H                              H     H      H

                                                            H      Br    H      H
      E   Butane                               F
                                                       H    C      C     C      C       H
                                                            H      H     H      H

                 H       H   H     H                         H     H      O       H
      G                                        H
          H      C       C   C     C     H             H     C     C      C       C      H

                 H       H   OH H                            H     H              H

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                                               NSC

2.4       Define the term functional group.                                                      (2)

2.5       Refer to the table of organic compounds on the previous page.

          Write down the letter/letters that represent(s) the following:

          2.5.1         Haloalkane                                                               (1)

          2.5.2         Ester                                                                    (1)

          2.5.3         Molecule with a general formula, CnH2n                                   (1)

          2.5.4         TWO pairs of organic molecules that are isomers                          (2)

2.6       Rewrite the identified pairs of isomers in QUESTION 2.5.4 and next to each,
          write down the TYPE of isomer to which each pair belongs.                              (2)

2.7       Write down the structural formulae of:

          2.7.1         Compound E                                                               (2)

          2.7.2         A functional group of compound A                                         (2)

2.8       Write down the IUPAC names of the compounds represented by the following
          letters:

          2.8.1         F                                                                        (2)

          2.8.2         H                                                                        (2)

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Technical Sciences/P2                             9                       DBE/November 2019
                                                 NSC

2.9       Polymers are organic molecules used in everyday life.

          2.9.1         Define the term polymer.                                                  (2)

          2.9.2         Identify TWO objects in the pictures below that are made from
                        polymers.

                                      Balloons                    Pine furniture

                                     Paper                        Plastic bottles

                              Wooden telephone poles         Cardboard boxes

                                                                                                    (2)
                                                                                                    [26]

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                                                   NSC

QUESTION 3 (Start on a new page.)

The table below shows TWO organic compounds with their corresponding boiling
points.

           ORGANIC COMPOUNDS                             BOILING POINT

                           A

               H       H       H       H
                                                              -0,5 °C
       H       C       C       C       C       H
               H       H       H       H

                           B

                   H       H       H
           H       C       C       C       H
                                                             -11,7 °C
                   H               H
                   H       C       H
                           H

3.1        Identify the TYPE of intermolecular force of the compounds in the table
           above.                                                                             (1)

3.2        Explain the difference in the boiling points of A and B. Refer to CHAIN
           LENGTH, STRENGTH OF INTERMOLECULAR FORCES and ENERGY.                              (3)

3.3        Define the term melting point.                                                     (2)

3.4        Which ONE of the two compounds in the table has a higher melting point?            (1)

3.5        Explain the answer in QUESTION 3.4.                                                (2)

3.6        How does the vapour pressure of A compare to the vapour pressure of B?
           Write only HIGHER THAN, LOWER THAN or THE SAME AS.                                 (1)
                                                                                              [10]

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Technical Sciences/P2                       11                           DBE/November 2019
                                           NSC

QUESTION 4 (Start on a new page.)

Butane can react with excess oxygen and is used as cigarette lighter fuel or in bottled
gas for cooking.

4.1       Write down the TYPE of reaction that takes place when butane is used as a
          fuel.                                                                                  (1)

4.2       Consider the flow diagram below and answer the questions that follow.

                       Alcohol B             Reaction 1
                  (secondary alcohol)                                  Compound C

                     Compound A
                                                            +HBr
                                                          Reaction 2
                        +H2

          Write down the NAME/TYPE of the following:

          4.2.1         Reaction 1                                                             (1)

          4.2.2         Reaction 2                                                             (1)

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Technical Sciences/P2                           12                      DBE/November 2019
                                               NSC

4.3       Write down the NAME of the following:

          4.3.1         Compound A                                                             (2)

          4.3.2         Alcohol B                                                              (2)

          4.3.3         Compound C                                                             (2)

4.4       Name ONE reaction condition for reaction 1.                                          (1)
                                                                                               [10]

QUESTION 5 (Start on a new page.)

The diagram below represents an electrochemical cell used in the decomposition of
copper(ll)chloride.

5.1       Identify the TYPE of electrochemical cell represented in the diagram above.          (1)

5.2       What energy conversion takes place in this cell?                                     (2)

5.3       Define the term electrolyte.                                                         (2)

5.4       What type of ions are Cu2+ ? Write only ANIONS or CATIONS.                           (1)

5.5       Write down the balanced half reactions that occur at the:

          5.5.1         Cathode                                                                (2)

          5.5.2         Anode                                                                  (2)

5.6       Define the term oxidising agent.                                                     (2)

5.7       Identify the reducing agent in this cell.                                            (1)

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Technical Sciences/P2                         13                         DBE/November 2019
                                             NSC

5.8       In which direction will electrons flow in the external circuit? Write only FROM
          THE CATHODE TO THE ANODE or FROM THE ANODE TO THE
          CATHODE.                                                                              (1)

5.9       Write down the overall net cell reaction.                                             (3)
                                                                                                [17]

QUESTION 6 (Start on a new page.)

The picture below is a representation of an electrochemical process operating similarly
to a galvanic cell, where an underground iron pipe is connected to the magnesium bar
to prevent the iron pipe from rusting.

6.1       Define the term galvanic cell.                                                        (2)

6.2       Which electrode is the anode?                                                         (1)

6.3       What substance in the picture acts as the salt bridge?                                (1)

6.4       Write down TWO functions of a salt bridge.                                            (2)

6.5       What will happen to the mass of magnesium during the process? Write only
          INCREASES, DECREASES or STAYS THE SAME.                                  (1)

6.6       Explain the answer to QUESTION 6.5.                                                   (2)

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                                                  NSC

6.7       Write down the balanced net reaction.                                                     (3)

6.8       Calculate the emf of the cell.                                                            (4)

6.9       Eskom is the main supplier of electrical energy in South Africa.

          Write down:

          6.9.1         THREE alternative sources of energy used in South Africa                    (3)

          6.9.2         THREE advantages of biodiesel                                               (3)
                                                                                                    [22]

QUESTION 7 (Start on a new page.)

7.1       State the law of reflection of light.                                                      (2)

7.2       How should a ray of light be incident on a rectangular glass block for it to
          emerge from the opposite side of the block without being refracted?                        (1)

7.3       An incident light ray, OA, enters a rectangular glass block from air with an
          incidence angle (i) of 55°. The angle of refraction (r) is 40°. After refraction, the
          ray of light continues in the glass block and strikes the boundary at B,
          emerging into air.

          Draw a fully labelled ray diagram (not to scale) to show the path of the light ray
          through the rectangular glass block. Indicate the magnitude of all angles.                 (6)

7.4       The magnitude of the critical angle in the diagram below is 55°.

                                                          Less optical dense medium
                                                  1       More optical dense medium
                                                      2

          7.4.1         Define the term critical angle.                                             (2)

          7.4.2         Which angle represents the critical angle? Write down only 1 or 2.          (1)

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Technical Sciences/P2                            15                         DBE/November 2019
                                                NSC

          The incident angle is increased to 65°.

          7.4.3         What will be observed? Write only THE RAY WILL MOVE OUT OF
                        THE MORE OPTICAL DENSE MEDIUM or THE RAY WILL BE
                        REFLECTED BACK INTO THE MORE OPTICAL DENSE
                        MEDIUM.                                                                    (1)

          7.4.4         Write the NAME of the phenomenon observed in QUESTION 7.4.3.               (1)

          7.4.5         Define the phenomenon in QUESTION 7.4.4.                                   (2)

7.5       Learners performed an experiment to investigate the properties of an image in
          a flat mirror.

          7.5.1         What TYPE of image is formed?                                              (1)

          7.5.2         Compare the image and the object with regard to the following:

                        (a)   Distance in front and behind the mirror                              (1)

                        (b)   Size                                                                 (1)
                                                                                                   [19]

QUESTION 8 (Start on a new page.)

8.1       Name the phenomenon where white light is spread into its component
          colours.                                                                                 (1)

8.2       What attributes of light causes it to spread out into different colours?                 (2)

8.3       What is the NAME given to a range of colours observed when white light
          spreads out into its component colours?                                                  (1)

8.4       Which photons between YELLOW and GREEN light have higher energy?
          Write only YELLOW LIGHT or GREEN LIGHT.                                                  (1)

8.5       Explain the answer to QUESTION 8.4.                                                      (2)

8.6       A girl directs a thin beam of light from different directions onto a convex lens
          held vertically. At a particular point in the lens the ray of light passes straight
          through the lens.

          Give a reason for this observation.                                                      (1)

8.7       What type of lens has a centre that is thinner than the edges?                           (1)

8.8       Draw a ray diagram to show the POSITION and NATURE of the image
          formed when the object is placed beyond F of the lens, as described in
          QUESTION 8.7.                                                                            (5)
                                                                                                   [14]

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                                              NSC

QUESTION 9 (Start on a new page.)

9.1       Define a photon.                                                                   (2)

9.2       Identify the TYPE of electromagnetic wave that is applicable to the function or
          use depicted in each of the pictures below. Write down the NAME of the
          electromagnetic wave next to the letter, e.g. H – visible light waves.

                      A. TV remote control          B. Taking pictures of broken bones

                     C. Tanning on a sunbed               D. Nuclear explosion

                     E. Telecommunication                    F. Cooking food

                                                                                             (6)

9.3       The wavelength of one of the waves is 600 nm. Calculate the energy of its
          photon.                                                                            (4)
                                                                                             [12]

                                                                                 TOTAL:      150

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Technical Sciences/P2                                                            DBE/November 2019
                                                      NSC

TABLE 1: PHYSICAL CONSTANTS

               NAME                            SYMBOL                   VALUE
 Standard pressure                               p           1,01 x 105 Pa
 Standard temperature                            T           0 oC/273 K
 Speed of light in a vacuum                      c            3,0 x 108 m·s-1
 Planck's constant                               h            6,63 x 10-34 J·s

TABLE 2: WAVES, SOUND AND LIGHT

                                                          1
 vf                                                T
                                                          f
                         c
 E  hf     or E  h
                         

TABLE 3: FORMULAE

 Eθcell  Eθcathode  Eθanode

 Eθcell  Ereduction
           θ
                      Eθoxidation

 Eθcell  Eθoxidisingagent  Ereducing
                              θ
                                       agent

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Technical Sciences/P2                                                                                              DBE/November 2019
                                                                                    NSC

                                             TABLE 4A: STANDARD REDUCTION POTENTIALS

                                                                           Half-reactions                 Eθ (V)
                                                F2(g) + 2e                        ⇌   2F                + 2,87
                                                Co + e
                                                                                         2+
                                                   3+
                                                                                   ⇌   Co                 + 1,81
                                                H2O2 + 2H +2e                     ⇌
                                                           +
                                                                                       2H2O               +1,77
                                                       
                                                MnO 4 + 8H + 5e                                          + 1,51
                                                                                            2+
                                                                       +
                                                                                   ⇌   Mn        + 4H2O
                                                                                            
                                                Cℓ2(g) + 2e                        ⇌   2Cℓ                + 1,36
                                                     2
                                                Cr2O 7 + 14H + 6e                                        + 1,33
                                                                                           3+
                                                            +
                                                                                   ⇌   2Cr + 7H2O
                                                                             
                                                O2(g) + 4H + 4e
                                                                   +
                                                                                   ⇌   2H2O               + 1,23
                                                MnO2+ 4H + 2e
                                                                                          2+
                                                            +
                                                                                   ⇌   Mn + 2H2O          + 1,23
                                                          
                                                  2+
                                                Pt + 2e                            ⇌   Pt                 + 1,20
                                                Br2(ℓ) + 2e                       ⇌   2Br               + 1,07
                                                     
                                                NO 3 + 4H + 3e                                           + 0,96
                                                            +
                                                                                   ⇌   NO(g) + 2H2O
                                                               
                                                  2+
                                                Hg + 2e                            ⇌   Hg(ℓ)              + 0,85
                                                Ag + e                            ⇌
                                                  +
                                                                                       Ag                 + 0,80
                                                    
                                                NO 3 + 2H + e                                            + 0,80
                                                         +
                                                                                   ⇌   NO2(g) + H2O
                                                                                           2+
                                                  3+
                                                Fe + e                             ⇌   Fe                 + 0,77
                                                O2(g) + 2H + 2e                   ⇌
                                                            +
                                                                                       H2O2               + 0,68
                                                        
                                                I2 + 2e                            ⇌   2I                + 0,54
                                                Cu + e                            ⇌
                                                    +
                                                                                       Cu                 + 0,52

                                                                                                                        Increasing reducing ability/
                                                SO2 + 4H + 4e                     ⇌
                                                          +
                                                                                       S + 2H2O           + 0,45

              Increasing oxidising ability
                                                2H2O + O2 + 4e                    ⇌   4OH               + 0,40
                                                Cu + 2e                           ⇌
                                                    2+
                                                                                       Cu                 + 0,34
                                                   2
                                                SO 4 + 4H + 2e                    ⇌                      + 0,17
                                                                   +
                                                                                       SO2(g) + 2H2O
                                                                                           +
                                                  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                           ⇌                       1,66
                                                   3+
                                                                                       Aℓ
                                                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

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                                         TABLE 4B: STANDARD REDUCTION POTENTIALS

                                                                           Half-reactions                      Eθ (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                                   ⇌                        1,66
                                              3+
                                                                                           Aℓ
                                            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
                                            Fe + 2e                                   ⇌                        0,44
                                               2+
                                                                                           Fe
                                            Cr + e
                                                                                              2+
                                                                                       ⇌                        0,41
                                               3+
                                                                                           Cr

          Increasing oxidising ability
                                            Cd + 2e                                   ⇌                        0,40
                                                2+
                                                                                           Cd
                                            Co + 2e                                   ⇌                        0,28
                                                2+

                                                                                                                               Increasing reducing ability
                                                                                           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
                                                                                             2+
                                               3+
                                            Fe + e                                     ⇌   Fe                  + 0,77
                                                  
                                            NO 3 + 2H + e
                                                         +
                                                                                       ⇌   NO2(g) + H2O        + 0,80
                                                           
                                                 +
                                            Ag + e                                     ⇌   Ag                  + 0,80
                                            Hg + 2e                                   ⇌
                                              2+
                                                                                           Hg(ℓ)               + 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
                                                                                           2+
                                            MnO 4          + 8H + 5e
                                                                       +
                                                                                       ⇌   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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