# Physical Sciences Grade 12 Paper 2 NSC June 2021 Memo

> Grade 12 Physical Sciences Paper 2 memorandum from the NSC June Exam 2021, 19 pages. Read online or download the free PDF.

- Page: https://www.hlayiso.com/library/physical-sciences-p2-may-june-2021-mg-afr-eng/4229f957-c431-4066-b20c-376bcbb9de9b
- Updated: 2026-10-29
- Subject: Physical Sciences
- Grade: Grade 12
- Document type: Memorandum
- Year: 2021
- Exam period: NSC June Exam
- Paper: 2
- Curriculum: CAPS
- Pages: 19

Breadcrumbs: [Home](https://www.hlayiso.com/) › [Library](https://www.hlayiso.com/library) › [Grade 12](https://www.hlayiso.com/library/grade-12) › [Physical Sciences](https://www.hlayiso.com/library/grade-12/physical-sciences) › [Physical Sciences Grade 12 Paper 2 NSC June 2021 Memo](https://www.hlayiso.com/library/physical-sciences-p2-may-june-2021-mg-afr-eng/4229f957-c431-4066-b20c-376bcbb9de9b)

## About this document

Physical Sciences · Grade 12 · NSC June Exam · 2021. Memorandum. Read online or download the PDF.

Read it free online on the page above; download the PDF from there.

## Document text

Text extracted from the PDF. Layout, diagrams and tables may not survive extraction.

### Page 1

Downloaded from hlayiso.com

             SENIOR CERTIFICATE EXAMINATIONS/
         NATIONAL SENIOR CERTIFICATE EXAMINATIONS
               SENIORSERTIFIKAAT-EKSAMEN/
          NASIONALE SENIORSERTIFIKAAT-EKSAMEN

                      PHYSICAL SCIENCES: CHEMISTRY (P2)
                      FISIESE WETENSKAPPE: CHEMIE (V2)

                                          2021

                      MARKING GUIDELINES/NASIENRIGLYNE

                                                                 MARKS/PUNTE: 150

                     These marking guidelines consist of 19 pages./
                      Hierdie nasienriglyne bestaan uit 19 bladsye.

Copyright reserved/Kopiereg voorbehou                    Please turn over/Blaai om asseblief

### Page 2

Downloaded from hlayiso.com
Physical Sciences/P2/Fisiese Wetenskappe/V2      2                                         DBE/2021
                           SC/NSC/SS/NSS – Marking Guidelines/Nasienriglyne

QUESTION 1/VRAAG 1

1.1      C                                                                                             (2)

1.2      D                                                                                             (2)

1.3      C                                                                                             (2)

1.4      B                                                                                             (2)

1.5      D                                                                                             (2)

1.6      C                                                                                             (2)

1.7      B                                                                                             (2)

1.8      B                                                                                             (2)

1.9      A                                                                                             (2)

1.10     B                                                                                              (2)
                                                                                                         [20]

Copyright reserved/Kopiereg voorbehou                              Please turn over/Blaai om asseblief

### Page 3

Downloaded from hlayiso.com
Physical Sciences P2/Fisiese Wetenskappe V2        3                                     DBE/2021
                         SCE/NSC/SSE/NSS – Marking Guidelines/Nasienriglyne

QUESTION 2/VRAAG 2

2.1
2.1.1    F                                                                                             (1)

2.1.2    B&F                                                                                           (1)

2.1.3    C                                                                                             (1)

2.2
2.2.1    Haloalkane / alkyl halide 
         Haloalkaan/alkielhalied                                                                        (1)

2.2.2    3,5-dibromooctane 
         3,5-dibroomoktaan
         Marking criteria/Nasienkriteria:
          Octane/Oktaan 
          Dibromo/Dibroom 
          Substituents (dibromo) correctly numbered, hyphens, commas correctly used./
            Substituente (dibroom) korrek genommer, koppeltekens en kommas korrek
            gebruik.                                                                                   (3)

2.3
2.3.1     Pentan-3-one                          Marking criteria/Nasienkriteria:
          Pentan-3-oon                             Pentanone/pentanoon 
          OR/OF                                    Correct position of functional group. 
          3-pentanone                             Korrekte posisie van funksionele groep.
          3-pentanoon                                                                                   (2)

2.3.2    3-methylbutan-2-one/3-metielbutan-2-oon
         OR/OF
         3-methylbutanone/3-metielbutanoon
         OR/OF
         methylbutanone/metielbutanoon
         OR/OF
         3-methyl- 2-butanone/3-metiel-2-butanoon                                                     (2)

2.4
2.4.1    Hexyl methanoate 
         Heksielmetanoaat                                                                               (2)

2.4.2       O                                      O
                                 OR/OF
            C     O    C                      R     C    O    R
                                                                                                        (1)

2.5
2.5.1    Cracking/Elimination 
         Kraking/eliminasie                                                                             (1)

2.5.2    C7H16                                                                                        (2)

Copyright reserved/Kopiereg voorbehou                             Please turn over/Blaai om asseblief

### Page 4

Downloaded from hlayiso.com
Physical Sciences P2/Fisiese Wetenskappe V2        4                                     DBE/2021
                         SCE/NSC/SSE/NSS – Marking Guidelines/Nasienriglyne

2.5.3         H       H                                    Notes/Aantekeninge
                                                             Functional group/Funksionele
        H     C C     C H                                     groep: 
                                                              Whole structure correct/Hele
              H   H                                            struktuur korrek:                        (2)
                                                                                                        [19]

QUESTION 3/VRAAG 3

3.1       Marking guidelines/Nasienkriteria:
          If any one of the underlined key phrases in the correct context is omitted, deduct 1
          mark./Indien enige van die onderstreepte frases in die korrekte konteks uitgelaat is,
          trek 1 punt af.

         The pressure exerted by a vapour at equilibrium with its liquid in a closed
         system. 
         Die druk uitgeoefen deur 'n damp in ewewig met sy vloeistoffase in 'n geslote
         sisteem.                                                                                       (2)

3.2      Functional group/Type of intermolecular forces/Homologous series 
         Funksionele groep/Tipe intermolekulêre kragte/Homoloë reeks                                    (1)

3.3      B                                                                                             (1)

3.4       Marking criteria/Nasienkriteria
             State hydrogen bonding in A./Noem waterstofbinding in A. 
             State dipole-dipole forces in B./Noem dipool-dipoolkragte in B.
             Compare strengths of IMFs./Vergelyk sterktes van IMKe. 
             Compare energies required./Vergelyk energieë benodig. 
             Compound A/butan-1-ol has hydrogen bonding (dipole-dipole and
              London forces) between molecules. 
             Compound B/butan-2-one has dipole-dipole forces (and London forces)
              between molecules. 
             Intermolecular forces in compound A/butan-1-ol are stronger than
              intermolecular forces in compound B/butan-2-one. 
              OR
              Intermolecular forces in compound B/butan-2-one are weaker than
              intermolecular forces in compound A/butan-1-ol. 
             More energy is needed to overcome/break intermolecular forces in
              compound A/butan-ol than in compound B/butan-2-one. 

             Verbinding A/butan-1-ol het waterstofbindings (dipool-dipoolkragte en
              Londonkragte) tussen molekule.
             Verbinding B/butan-2-oon het dipool-dipoolkragte (en London kragte)
              tussen molekule. 
             Intermolekulêre kragte in verbinding A/butan-1-ol is sterker as
              intermolekulêre kragte in verbinding B/butan-2-oon.
              OF
              Intermolekulêre kragte in verbinding B/butan-2-oon is swakker as
              intermolekulêre kragte in verbinding A/butan-1-ol.
             Meer energie is nodig om intermolekulêre kragte te oorkom/breek in
              verbinding A/butan-1-ol as in verbinding B/butan-2-oon.                                   (4)

Copyright reserved/Kopiereg voorbehou                             Please turn over/Blaai om asseblief

### Page 5

Downloaded from hlayiso.com
Physical Sciences/P2/Fisiese Wetenskappe/V2      5                                                  DBE/2021
                           SC/NSC/SS/NSS – Marking Guidelines/Nasienriglyne

3.5
3.5.1       Boiling point (of compound A/butan-1-ol) 
            Kookpunt (van verbinding A/butan-1-ol)                                                                (1)

3.5.2       Gas                                                                                                  (1)

3.5.3                                                                  Marking criteria/Nasienkriteria:
                                                           A            Curve C starts below curve
                                                                            A/Kurwe C begin onder

        Vapour pressure (kPa)
                                                                 C          kurwe A. 
                                                                        Curve C remains below
                                                                          curve A/ Kurwe C bly onder
                                101,3                                       kurwe A. 
                                                                       Accept/Aanvaar

           Dampdruk (kPa)
                                                                        If C is labelled as B / Indien
                                                                            C as B benoem is
                                                                        If graph below graph A is
                                                                            unlabelled /Indien grafiek
                                        Temperature/Temperatuur (°C)        onder grafiek A nie
                                                                            benoemis nie
                                                                       Note/Let Wel
                                                                       If both graphs unlabelled / Indien
                                                                       beide grafiek nie benoem is nie:
                                                                       0 marks / 0 punte                           (2)
                                                                                                                  [12]

Copyright reserved/Kopiereg voorbehou                                       Please turn over/Blaai om asseblief

### Page 6

Downloaded from hlayiso.com
Physical Sciences P2/Fisiese Wetenskappe V2        6                                     DBE/2021
                         SCE/NSC/SSE/NSS – Marking Guidelines/Nasienriglyne

QUESTION 4/VRAAG 4

4.1
4.1.1     Heat/sunlight/ultraviolet light/radiation/light 
          Hitte/sonlig/ultravioletlig/straling/lig                                                      (1)

4.1.2     HBr/hydrogen bromide/waterstofbromied                                                        (1)

4.1.3     Hydrolysis/hidrolise                                                                         (1)

4.1.4     H2O/water
          Accept/Aanvaar
          hydrogen oxide/waterstofoksied

          OR/OF
          NaOH/KOH/LiOH/sodium hydroxide/potassium hydroxide/lithium hydroxide
          NaOH/KOH/LiOH/Natriumhidroksied/kaliumhidroksied/litiumhidroksied                             (1)

4.1.5     2-bromopropane 
          2-bromopropaan                                                                                (2)

4.2      Marking criteria/Nasienkriteria:
         (Mark bullets independently. / Sien kolpunte onafhanklik na.)
            React chloroethane with (conc) NaOH or NaOH in ethanol. 
            Indicate heat/Δ (on the arrow) or as a reactant in the reaction of chloroethane. 
            Correct condensed formula for ethene as product.
            Product NaCℓ in the reaction of chloroethane. 
            Product H2O in the reaction of chloroethane. 
            React ethene with H2.
            Indicate Pt on the arrow of / at the reaction of ethene with H2. 
            Correct condensed formula of ethane as product. 
             .
            Reageer chloroetaan met (gekons) NaOH of NaOH in etanol.
            Dui hitte/Δ (op die pyl) of as ‘n reaktant in die reaksie van chloroetaan. 
            Korrekte gekondenseerde formule vir eteen as produk. 
            Produk NaCℓ in die reaksie van chloroetaan.
            Produk H2O in die reaksie van chloroetaan.
            Reageer eteen met H2 
            Dui Pt aan op die pyl / by die reaksie van eteen met H2. 
            Korrekte gekondenseerde formule vir etaan as produk. 

                  + NaOH (in ethanol/etanol)           
         CH3CH2Cℓ + (conc/gekons) NaOH                ∆      CH2CH2  + NaCℓ  + H2O 

                              Pt 
         CH2CH2 + H2                CH3CH3 
         Note/Let wel
         Any additional reactants or products: Deduct one mark per reaction
         Enige addisionele reaktanse of produkte: Trek een punt af per reaksie                           (8)
                                                                                                        [14]

Copyright reserved/Kopiereg voorbehou                             Please turn over/Blaai om asseblief

### Page 7

Downloaded from hlayiso.com
Physical Sciences/P2/Fisiese Wetenskappe/V2      7                                         DBE/2021
                           SC/NSC/SS/NSS – Marking Guidelines/Nasienriglyne

QUESTION 5/VRAAG 5

5.1       NOTE/LET WEL
          Give the mark for per unit time only if in context of reaction rate.
          Gee die punt vir per eenheidtyd slegs indien in konteks met reaksietempo.
          ANY ONE/ENIGE EEN
           Change in concentration  of products/reactants per (unit) time. 
            Verandering in konsentrasie van produkte/reaktanse per (eenheid)tyd.
             Change in amount/number of moles/volume/mass of products or reactants
              per (unit) time.
              Verandering in hoeveelheid/getal mol/volume/massa van produkte of
              reaktanse per (eenheid)tyd.
             Amount/number of moles/volume/mass of products formed/reactants used
              per (unit) time.
              Hoeveelheid/getal mol/volume/massa van produkte gevorm/reaktanse
              gebruik per (eenheid)tyd.
             Rate of change in concentration/amount/number of moles/volume/mass.
              Tempo van verandering in konsentrasie/ hoeveelheid/getal mol/ volume/
              massa.  (2 or/of 0)                                                                      (2)
5.2        Time/tyd 
           Volume of gas/CO2/carbon dioxide (in gas syringe)
            Volume gas/CO2/koolstofdioksied (in gasspuit)
          OR/OF
           Time taken for Aℓ2(CO3)3 to be used up. 
            Tyd geneem vir die Aℓ2(CO3)3 om opgebruik te word.

          Accept/Aanvaar
          Measure volume of gas/CO2 at regular time intervals. 
          Meet volume van gas/CO2 met gereelde tydintervalle.                                            (2)
5.3       Experiment II/Eksperiment II:
           More (HCℓ) particles per unit volume./More particles with correct
             orientation. 
           More effective collisions per unit time./Higher frequency of effective
             collisions. 
           Higher reaction rate. 
             Meer (HCℓ)-deeltjies per eenheid volume./Meer deeltjies met korrekte
              oriëntasie.
             Meer effektiewe botsings per eenheid tyd./Hoër frekwensie van effektiewe
              botsings.
             Hoër reaksietempo.                                                                         (3)

Copyright reserved/Kopiereg voorbehou                              Please turn over/Blaai om asseblief

### Page 8

Downloaded from hlayiso.com
Physical Sciences P2/Fisiese Wetenskappe V2      8                               DBE/2021
                         SCE/NSC/SSE/NSS – Marking Guidelines/Nasienriglyne

          OR/OF
          Experiment I/Eksperiment I:
           Less (HCℓ) particles per unit volume. 
           Less effective collisions per unit time./Lower frequency of effective
             collisions. 
           Lower reaction rate. 
             Minder (HCℓ) deeltjies per eenheidvolume.
             Minder effektiewe botsings per eenheidtyd./ Laer frekwensie van
              effektiewe botsings.
             Laer reaksietempo.

5.4       OPTION 1/OPSIE 1                           Marking criteria/Nasienkriteria
                                   n                 Substitute average rate and ∆t./
          ave rate/gem tempo = -                        Vervang gemiddelde tempo en ∆t. 
                                   t
                                                      Substitute/Vervang ∆n. 
                        n  0,016 
          4,4 x 10-3 = - f                            Final answer/Finale antwoord:
                         2,5 ( 0)                      0,005 (mol) 
                                      
          n[Aℓ2(CO3)3] = 0,005 (mol)         NOTE/LET WEL
          OPTION 2/OPSIE 2                     Accept negative answers when the
                                 n             negative sign in front of the formula is
          ave rate/gem tempo =                  omitted./Aanvaar negatiewe antwoord
                                 t             wanneer die negatiewe teken voor die
                  -3   n                       formule uitgelaat is.
          4,4 x 10 =
                       2,5                     Do not penalise if initial and final mole
                                               values or time values are swopped. /
          Δn[Aℓ2(CO3)3] = 0,016 – 0,011        Moenie penaliseer indien aanvanklike
                       = 0,005 mol             en finale molwaardes omgeruil is nie.
          OPTION 3/OPSIE 3
          With reference to CO2/Met verwysing na CO2
                                 n
          ave. rate/gem tempo =
                                  t
                       n
          4,4 x 10-3 =
                       2,5
                                      
          Δn(CO2) = 0,011 mol

          n(CO2) : n(Aℓ2(CO3)3
            3    :    1
           0,011 : 3,67 x 10-3 mol 

          n(Aℓ2(CO3)3 left/oor = 0,016 - 3,67 x 10-3 = 1,23 x 10-2 mol 

Copyright reserved/Kopiereg voorbehou                             Please turn over/Blaai om asseblief

### Page 9

Downloaded from hlayiso.com
Physical Sciences P2/Fisiese Wetenskappe V2      9                               DBE/2021
                         SCE/NSC/SSE/NSS – Marking Guidelines/Nasienriglyne

          OPTION 4/OPSIE 4
          With reference to HCℓ/Met verwysing na HCℓ
                                n
          ave. rate/gem tempo =
                                t
                       n
          4,4 x 10-3 =     
                       2,5
                                        
          Δn(HCℓ) = 0,011 mol

                          0,011
          n[Aℓ2(CO3)3] =         = 0,0018 mol 
                             6
          n[Aℓ2(CO3)3] left/oor = 0,016 – 0,0018 = 0,0142 mol 
          OPTION 5/OPSIE 5
          With reference to AℓCℓ3/Met verwysing na AℓCℓ3
                                   n
          ave. rate/gem tempo =
                                    t
                        n
          4,4 x 10-3 =       
                       2,5
                                       
          Δn(AℓCℓ3) = 0,011 mol

          n[Aℓ2(CO3)3] = 0,0055 mol 

          n[Aℓ2(CO3)3] left/oor = 0,016 – 0,0055 = 0,0105 mol                                          (3)

5.5       Marking criteria/Nasienkriteria:
           Use mol ratio/Gebruik molverhouding: n(CO2) : n(Aℓ2(CO3)3) = 3 : 1 
                                  3     -1      3    -1    V
           Substitute 24 000 cm ∙mol /24 dm ∙mol in n =       or in ratio. 
                                                           VM
                                                          V
             Vervang 24 000 cm3∙mol-1/24 dm3∙mol-1 in n =     of in verhouding.
                                                          VM
           Final answer/Finale antwoord: 1 152 cm3 / 1,152 dm3 
          OPTION 1/OPSIE 1                        OPTION 2/OPSIE 2
          n(CO2) = 3n[Aℓ2(CO3)3]                  n(CO2) = 3n[Aℓ2(CO3)3]
                 = 3(0,016)                              = 3(0,016) 
                 = 0,048 mol                              = 0,048 mol
                    V
          n(CO2) =                                1 mol ……………….24 000 cm3
                    VM
                                                  0,048 mol ………….V
                       V
           0,048 =                                         0,048  24000
                     24000                        V(CO2) =                    
                             3           3                          1
          V(CO2) = 1 152 cm (1,152 dm ) 
                                                          = 1 152 cm3 (1,152 dm3)                       (3)
                                                                                                        [13]

Copyright reserved/Kopiereg voorbehou                             Please turn over/Blaai om asseblief

### Page 10

Downloaded from hlayiso.com
Physical Sciences P2/Fisiese Wetenskappe V2      10                                          DBE/2021
                         SCE/NSC/SSE/NSS – Marking Guidelines/Nasienriglyne

QUESTION 6/VRAAG 6

6.1      (The stage in a chemical reaction when the) rate of forward reaction equals
         the rate of reverse reaction. 
         (Die stadium in 'n chemiese reaksie wanneer die) tempo van die voorwaartse
         reaksie gelyk is aan die tempo van die terugwaartse reaksie.         (2 or/of 0)
         OR/OF
         (The stage in a chemical reaction when the) concentrations of reactants and
         products remain constant.
         (Die stadium in 'n chemiese reaksie wanneer die) konsentrasies van
         reaktanse en produkte konstant bly.                                (2 or/of 0)                     (2)

6.2
6.2.1     X
        - ANY ONE/ENIGE EEN
              The concentration of products increases (from 0 – 6 min.).
               Die konsentrasie van die produkte neem toe (van 0 - 6 min.).
              The concentration of reactants decreases (from 0 – 6 min.).
               Die konsentrasie van die reaktanse neem af (van 0 – 6 min.).
              No products were present initially. 
               Geen produkte was aanvanklik teenwoordig nie.
              The curve begins at zero./Die kurwe begin by nul.                                            (2)

6.2.2     Higher than/Hoër as                                                                              (1)

6.3      CALCULATIONS USING NUMBER OF MOLES
         BEREKENINGE WAT AANTAL MOL GEBRUIK

         Marking criteria/Nasienkriteria
          Calculate/Bereken mol HI: n(HI)ini/aanv. = 1(0,5). 
          Use mol ratio/Gebruik molverhouding: 2:1:1 / n(HI) = 2n(H2) = 2n(I2). 
          n(H2)equilibrium/ewewig = n(H2)formed/gevorm 
            n(I2)equilibrium/ewewig = n(I2)formed/gevorm
            Note: If Δn not shown award mark for equal nequilibrium
            Let wel: Indien Δn nie aangedui is nie, ken punt toe vir gelyke newewig
          n((HI)equilibrium/ewewig = n(HI)initial/aanvanklik - n(HI)change/verandering. 
          Divide n(HI)equil & n(H2)equil & n(H2)equil by 0,5 dm3. 
            Deel n(HI)ewewig & n(H2)ewewig & n(H2)ewewig deur 0,5 dm3.
          Correct Kc expression (formulae in square brackets). 
            Korrekte Kc-uitdrukking (formules in vierkanthakies).
          Substitute 0,04 into Kc expression. 
            Vervang 0,04 in Kc-uitdrukking.
          Substitute equilibrium concentrations in Kc expression. 
            Vervang ewewigskonsentrasies in Kc-uitdrukking.
          Final answer/Finale antwoord: 0,07 mol 
            Range/Gebied: 0,07 – 0,072 mol

Copyright reserved/Kopiereg voorbehou                                 Please turn over/Blaai om asseblief

### Page 11

Downloaded from hlayiso.com
Physical Sciences P2/Fisiese Wetenskappe V2      11                                           DBE/2021
                         SCE/NSC/SSE/NSS – Marking Guidelines/Nasienriglyne

          OPTION 1/OPSIE 1

          n(HI) = 1(0,5) = 0,5 mol

                                                           HI       H2      I2
           Initial quantity (mol)
                                                          0,5      0       0
           Aanvangshoeveelheid (mol)
           Change (mol)                                                              ratio 
                                                           2x        x      x
           Verandering (mol)                                                         verhouding
           Quantity at equilibrium (mol)/                                        
                                                     0,5-2x         x      x
           Hoeveelheid by ewewig (mol)
           Equilibrium concentration (mol∙dm-3)          0,5 - 2x    x      x        divide by 0,5 
           Ewewigskonsentrasie (mol∙dm-3)                  0,5      0,5    0,5       deel deur 0,5

               [H2 ][I2 ]               No KC expression, correct substitution/Geen Kc-
          Kc =            
                [HI] 2                                                                    8
                                        uitdrukking, korrekte substitusie: Max./Maks.
                      x     x                                                             9
                  ( )( )
                    0,5 0,5            Wrong KC expression /Verkeerde Kc-uitdrukking:
          0,04 =                                     6
                    0,5 - 2x 2          Max./Maks.
                  (           )                      9
                       0,5
             x = 0,071 mol 

          CALCULATIONS USING CONCENTRATION
          BEREKENINGE WAT KONSENTRASIE GEBRUIK
          Marking criteria/Nasienkriteria:
           Use initial/Gebruik aanvanklike c(HI) = 1 mol∙dm-3. 
           Use mol ratio/Gebruik molverhouding: 2 : 1: 1 / n(HI) = 2n(H2) = 2n(I2). 
           c(H2)equilibrium/ewewig = c(H2)formed/gevorm      
            c(I2)equilibrium/ewewig = c(I2)formed/gevorm
            Note: If Δc not shown award mark for equal cequilibrium
            Let wel: Indien Δc nie aangedui is nie, ken punt toe vir gelyke cewewig
           c(HI)equilibrium/ewewig = c(HI)initial - c(HI)change. 
           Correct Kc expression (formulae in square brackets). 
            Korrekte Kc-uitdrukking (formules in vierkanthakies).
           Substitution of 0,04 into Kc expression. 
            Vervang 0,04 in Kc-uitdrukking.
           Substitution of equilibrium concentrations into Kc expression. 
            Vervanging van ewewigskonsentrasies in Kc-uitdrukking.
           Multiply concentration by 0,5 dm3. 
            Vermenigvuldig konsentrasie met 0,5 dm3.
           Final answer/Finale antwoord: 0,07 mol 
             Range/Gebied: 0,07 to/tot 0,072 mol

Copyright reserved/Kopiereg voorbehou                               Please turn over/Blaai om asseblief

### Page 12

Downloaded from hlayiso.com
Physical Sciences P2/Fisiese Wetenskappe V2      12                                          DBE/2021
                         SCE/NSC/SSE/NSS – Marking Guidelines/Nasienriglyne

          OPTION 2/OPSIE 2

                                                         HI     H2         I2
                                          -3
             Initial concentration (mol∙dm )
                                                         1      0         0
             Aanvangskonsentrasie (mol∙dm-3)
             Change (mol∙dm-3)
                                                         2x      x          x
             Verandering (mol∙dm-3)
             Equilibrium concentration (mol∙dm-3)
             Ewewigskonsentrasie (mol∙dm-3)          1-2x       x          x 

              [H2 ][I2 ]
          Kc =                         No KC expression, correct substitution/Geen Kc-
               [HI] 2                                                                    8
                                        uitdrukking, korrekte substitusie: Max./Maks.
                   ( x )( x )                                                           9
          0,04 =               
                  (1  2x )2
                                        Wrong KC expression /Verkeerde Kc-uitdrukking:
               x = 0,143 mol∙dm-3                    6
                                        Max./Maks.
                                                     9
          n(I2) = cV
                = 0,143 x 0,5 
                = 0,072 mol                                                                               (9)

6.4
6.4.1     Both forward and reverse/Beide voorwaartse en terugwaartse                                      (1)
6.4.2    Positive/Positief 

           The forward reaction is favoured. 
            Die voorwaartse reaksie word bevoordeel.
          An increase in temperature favours the endothermic reaction. 
           'n Toename in temperatuur bevoordeel die endotermiese reaksie.
          The forward reaction is endothermic. 
           Die voorwaartse reaksie is endotermies.                                                          (4)
                                                                                                           [19]

Copyright reserved/Kopiereg voorbehou                                Please turn over/Blaai om asseblief

### Page 13

Downloaded from hlayiso.com
Physical Sciences P2/Fisiese Wetenskappe V2      13                                         DBE/2021
                         SCE/NSC/SSE/NSS – Marking Guidelines/Nasienriglyne

QUESTION 7/VRAAG 7

7.1      Standard solution/Standaardoplossing                                                             (1)

7.2
7.2.1    Marking criteria/Nasienkriteria:
                                                                         m      m      n
           Any one of the formulae/Enige een van die formules: c          /n   /c    
                                                                         MV     M      V
           Substitution of 40 g∙mol-1 into correct formula. 
            Vervanging van 40 g∙mol-1 in korrekte formule.
           Substitution of 0,25 dm3 into correct formula. 
            Vervanging van 0,25 dm3 in korrekte formule.
           Final answer/Finale antwoord: 0,2 mol∙dm-3 

         OPTION 1/OPSIE 1                             OPTION 2/OPSIE 2
             m                                           m
         c                                          n
            MV                                           M
                2
                                                            2
           40  0,25                                  
                                                            40            Any one formula/
          = 0,20 mol∙dm-3 
                                                       = 0,05 mol          enige formule 
                                                         n
                                                      c
                                                         V
                                                            0,05
                                                        
                                                            0,25 
                                                        = 0,20 mol∙dm-3                                   (4)

7.2.2    POSITIVE MARKING FROM 7.2.1./POSITIEWE NASIEN VAN 7.2.1.
         OPTION 1/OPSIE 1                OPTION 2/OPSIE 2

         [H3O+][OH-] = 1 x 10-14                      pOH = -log[OH-] 
         [H3O+](0,2) = 1 x 10-14                         = -log(0,2) 
         [H3O+] = 5 x 10-14 mol∙dm-3                      = 0,6989 (0,7)

         pH = -log[H3O+]                             pH + pOH = 14
            = -log(5 x 10-14)                              pH = 14 – 0,6989 
            = 13,30                                           = 13,30                                    (4)

Copyright reserved/Kopiereg voorbehou                                Please turn over/Blaai om asseblief

### Page 14

Downloaded from hlayiso.com
Physical Sciences P2/Fisiese Wetenskappe V2      14                                       DBE/2021
                         SCE/NSC/SSE/NSS – Marking Guidelines/Nasienriglyne

7.3      POSITIVE MARKING FROM QUESTION 7.2.
         POSITIEWE NASIEN VANAF VRAAG 7.2.
         Marking criteria/Nasienkriteria:
          Substitution to calculate n(NaOH)./Vervanging om n(NaOH) te bereken. 
          Use mol ratio/Gebruik molverhouding: n(HCℓ)excess/oormaat : n(NaOH) = 1 : 1. 
                                                    m
           Substitute/Vervang 100 g·mol-1 in n =     
                                                    M
           Use mol ratio Gebruik molverhouding: n(HCℓ)reacted/oormaat : n(CaCO3) = 2 : 1. 
           n(HCℓ)initial/aanvanklik = n(HCℓ) excess/oormaat + n(HCℓ) reacted/reageer 
           Substitute 0,05 dm3 to calculate either c(HCℓ)initial or c(HCℓ) reacted
            Vervang 0,05 dm3 om c(HCℓ)aanvanklik of c(HCℓ)reageer te bereken.
           Final answer/Finale antwoord: 0,7 mol∙dm-3 
            Range/Gebied: 0,70 to/tot 0,90 mol∙dm-3
         OPTION 1/OPSIE 1                           OPTION 2/OPSIE 2
         n(NaOH)used/gebruik = cbVb                                        25     2
                                                    n(NaOH)used/gebruik =           
                             = 0,2 x 0,025                               250 40
                             = 5 x 10-3 mol                             = 5 x 10-3 mol

                           n(HCℓ)excess/oormaat = n(NaOH) = 5 x 10-3 mol 

                       m
         n(CaCO3) =
                       M
                       1,5
                    =
                       100 
                    = 0,015 mol (0,02 mol)

          n(HCℓ)reacted/reageer = 2n(CaCO3) = 0,03 mol       (0,04 mol)

         n(HCℓ)ini/aanv. = 5 x 10-3 + 0,03 
                         = 0,035 mol (0,045 mol)
                           n
         c(HCℓ)ini/aanv =
                          V
                           0,035
                        =        
                            0,05
                        = 0,70 mol∙dm-3  (0,90 mol∙dm-3)

Copyright reserved/Kopiereg voorbehou                              Please turn over/Blaai om asseblief

### Page 15

Downloaded from hlayiso.com
Physical Sciences P2/Fisiese Wetenskappe V2      15                                             DBE/2021
                         SCE/NSC/SSE/NSS – Marking Guidelines/Nasienriglyne

         OPTION 3/OPSIE 3                              OPTION/OPSIE 4
         c a Va na                                     (NaOH)used/gebruik = cbVb
                                                                          = (0,2)(0,025)
         c b Vb nb
                                                                           = 0,005 mol
             c a (0,05)  1
                         
          (0,2)(0,025) 1                              n(HCℓ)excess/oormaat = n(NaOH)
                                                                           = 0,005 mol
         ca = c(HCℓ)excess/oormaat
                                                                                0,005
            = 0,1 mol·dm-3                             c(HCℓ)excess/oormaat =
                                                                                 0,05
                                                                             = 0,1 mol·dm-3

                        m
         n(CaCO3) =
                        M
                        1,5
                    =
                        100 
                    = 0,015 mol

         n(CaCO3) : n(HCℓ) = 1 : 2
         n(HCℓ)reacted/reageer = 2(0,015) 
                                = 0,03 mol
                                   n
         c(HCℓ)reacted/reageer =
                                   V
                                  0,03
                                =      
                                  0,05
                                = 0,6 mol·dm-3

         c(HCℓ)initial/aanvanklik = c(HCℓ)reacted/reageer + c(HCℓ)excess/oormaat
                                  = 0,6 + 0,1 
                                  = 0,7 mol·dm-3 
                                                                                                                (8)
                                                                                                               [17]

Copyright reserved/Kopiereg voorbehou                                    Please turn over/Blaai om asseblief

### Page 16

Downloaded from hlayiso.com
Physical Sciences P2/Fisiese Wetenskappe V2      16                                       DBE/2021
                         SCE/NSC/SSE/NSS – Marking Guidelines/Nasienriglyne

QUESTION 8/VRAAG 8

8.1
8.1.1     Gain of electrons./Opneem van elektrone.          (2 or/of 0)                                (2)

8.1.2    2H2O(ℓ) + 2e─  H2(g) + 2OH─(aq) 

         Ignore phases/Ignoreer fases.
         Marking criteria /Nasienkriteria:
           H2(g) + 2OH─(aq) ← 2H2O(ℓ) + 2e─          (2 )
                                                           2
           2H2O(ℓ) + 2e ⇌ H2(g) + 2OH (aq)
                           ─                 ─
                                                      ( 1    )
                                                          2
           H2(g) + 2OH─(aq) ⇌ 2H2O(ℓ) + 2e─             (0 )
                                                            2
                          ─                 ─              0
           2H2O(ℓ) + 2e ← H2(g) + 2OH (aq)               (     )
                                                             2
          Ignore if charge omitted on electron./Ignoreer indien lading weggelaat op
           elektron.
          If charge (-) omitted on OH─/Indien lading (-) weggelaat op OH─:
           Example/Voorbeeld: 2H2O(ℓ) + 2e─  H2(g) + 2OH(aq)              Max./Maks: 1
                                                                                         2                 (2)

8.1.3     2Na(s) + 2H2O(ℓ)   H2(g) + 2OH-(aq) + 2Na+(aq)                    Bal 

          OR/OF
          2Na(s) + 2H2O(ℓ)   H2(g) + 2NaOH(aq)                  Bal 

          Ignore phases/Ignoreer fases.
          Marking criteria/Nasienkriteria:
            Reactants           Products          Balancing 
             Reaktanse            Produkte           Balansering
            Ignore double arrows./Ignoreer dubbelpyle.
            Ignore phases/Ignoreer fases.
            Marking rule 6.3.10./Nasienreël 6.3.10.                                                      (3)

8.1.4     Formation of hydroxide ions / OH- / sodium hydroxide/base/ alkaline/ pH > 7 
          Vorming van hidroksied / OH- / natriumhidroksied / basis / alkalies / pH > 7                    (1)
                                            ─
8.1.5     Cu is a weaker reducing agent  than H2 (and OH─)  and H2O will not be
          reduced  (to H2 and OH─).
          Cu is 'n swakker reduseermiddel as H2 (and OH─) en H2O sal nie gereduseer
          word nie na H2 (en OH─).
                                                   ─
          OR/OF
          H2 (and OH-) are stronger reducing agent  than Cu and H2O will not be
          reduced(to H2 and OH-).
          H2 (en OH-) is 'n sterker reduseermiddel as Cu en H2O sal nie gereduseer
          word (na H2 en OH-).                                                                            (3)

Copyright reserved/Kopiereg voorbehou                              Please turn over/Blaai om asseblief

### Page 17

Downloaded from hlayiso.com
Physical Sciences P2/Fisiese Wetenskappe V2      17                                                  DBE/2021
                         SCE/NSC/SSE/NSS – Marking Guidelines/Nasienriglyne

8.2
8.2.1        Phase separator/boundary/difference 
             Fase skeiding/grens/verskil                                                                            (1)

8.2.2        Chemical (energy) to electrical (energy) 
             Chemiese (energie) na elektriese (energie)                                                             (1)

8.2.3       OPTION/OPSIE 1                          Notes/Aantekeninge
              
            E cell      
                     E reduction     
                                   E oxidation     Accept any other correct formula from the data
                                                      sheet./Aanvaar enige ander korrekte formule
                    = 0,77  - (-0,13)               vanaf gegewensblad.
              
            E cell = 0,90 V                         Any other formula using unconventional
                                                      abbreviations, e.g. Eθcell = EθOA - EθRA followed by
                                                      correct substitutions:/Enige ander formule wat
                                                      onkonvensionele afkortings gebruik bv.
                                                      Eθsel = EθOM - EθRM gevolg deur korrekte
                                                      vervangings: Max/Maks: 3
                                                                                    4
             OPTION/OPSIE 2
               Pb(s)  Pb2+(aq) + 2e-               0,13 (V) 
            
              2Fe3+(aq) + 2e-  2Fe2+(aq)            0,77 (V) 
                2+          3+                2+
              Pb (aq) + 2Fe (aq)  Pb(s) + 2Fe (aq) 0,90 V                                                          (4)
                                                                                                                    [17]

QUESTION 9/VRAAG 9

9.1          Electrolytic (cell)/Elektrolitiese (sel) 
        -
             Cells have a battery/DC power source/ /Electrical energy is converted to
             chemical energy. 
             Selle het batterye/GS kragbron/ Elektriese energie is omgeskakel na
             chemiese energie.                                                                                      (2)

9.2
9.2.1       2Cℓ─  Cℓ2 + 2e─ 
            Notes/Aantekeninge
            2Cℓ─ ⇌ Cℓ2 + 2e─ ( 1 )                       Cℓ2 + 2e─ ← 2Cℓ─ ( 2 )
                                    2                                             2
                     ─        ─   0                          ─             ─     0
            Cℓ2 + 2e ⇌ 2Cℓ (          )                  2Cℓ ← Cℓ2 + 2e        (     )
                                    2                                              2
             Ignore if charge omitted on electron./Ignoreer indien lading weggelaat op elektron.
             If charge (-) omitted on Cℓ─/Indien lading (-) weggelaat op Cℓ─:
               Example/Voorbeeld: 2Cℓ(aq)  Cℓ2(g) + 2e─ Max./Maks: 1
                                                                            2                                       (2)

Copyright reserved/Kopiereg voorbehou                                         Please turn over/Blaai om asseblief

### Page 18

Downloaded from hlayiso.com
Physical Sciences P2/Fisiese Wetenskappe V2      18                                      DBE/2021
                         SCE/NSC/SSE/NSS – Marking Guidelines/Nasienriglyne

9.2.2    Aℓ3+ + 3e─  Aℓ 
         Notes/Aantekeninge
         Aℓ3+ + 3e─ ⇌ Aℓ ( 1 )                        Aℓ ← Aℓ3+ + 3e─ ( 2 )
                                2                                              2
                         ─       0                                           0
         Aℓ ⇌ Aℓ + 3e
                 3+
                               (     )                   3+
                                                      Aℓ + 3e ← Aℓ         (     )
                                   2                                           2
          Ignore if charge omitted on electron./Ignoreer indien lading weggelaat op elektron.
          If charge (+) omitted on Aℓ3+ /Indien lading (+) weggelaat op Aℓ3+:
            Example/Voorbeeld: Aℓ3(aq) + 3e─  Aℓ(s) Max./Maks: 1
                                                                         2                              (2)

9.2.3     Cu/copper/koper                                                                              (1)

9.3       ANY ONE/ENIGE EEN
           The electrode/carbon/C reacts with oxygen. 
             Die elektrode/koolstof/C reageer met suurstof.
           C + O2  CO2
           Oxidation takes place./Electrons are lost.
             Oksidasie vind plaas./Elektrone word verloor.
           Oxygen corrodes the carbon electrode.
             Suurstof roes die koolstof elektrode.                                                      (1)
                                                                                                        [8]

QUESTION 10/VRAAG 10

10.1
10.1.1    Sulphur dioxide/SO2/swaweldioksied                                                           (1)

10.1.2    Sulphur trioxide/SO3/swaweltrioksied                                                         (1)

10.1.3    Vanadium pentoxide/V2O5/ Vanadium(V) oxide 
          Vanadiumpentoksied/Vanadium(V) oksied                                                         (1)

10.1.4   H2SO4 + 2NH3   (NH4)2SO4                bal 
         Marking guidelines/Nasienkriteria:
          Reactants          Products              Balancing 
            Reaktanse         Produkte              Balansering 
            Ignore/Ignoreer → and phases / en fases
            Marking rule 6.3.10/Nasienreël 6.3.10                                                      (3)

10.2
10.2.1    The ratio of nitrogen (N), phosphorous (P) and potassium (K) in a
          fertiliser./The ratio of the primary nutrients 
          Die verhouding van stikstof (N), fosfor (P) en kalium (K) in die kunsmis. / Die
          verhouding van primêre nutriënte.                                                             (1)

Copyright reserved/Kopiereg voorbehou                             Please turn over/Blaai om asseblief

### Page 19

Downloaded from hlayiso.com
Physical Sciences/P2/Fisiese Wetenskappe/V2     19                                     DBE/2021
                           SC/NSC/SS/NSS – Marking Guidelines/Nasienriglyne

10.2.2    OPTION 1/OPSIE 1
          Mass N in 4 kg NH4NO3 / Massa N in 4 kg NH4NO3
                   28
          m(N) =      x4
                   80
               = 1,4 kg

          m(K) = 2m(N) 
               = 2,8 kg

          m(P) = 3m(N) 
               = 4,2 kg

          m(fertiliser/kunsmis) = 1,4 + 2,8 + 4,2
                                = 8,4 kg 
          OPTION 2/OPSIE 2
          Mass N in 4 kg NH4NO3/Massa N in 4 kg NH4NO3:
                 28
          m(N) =     x4
                 80
               = 1,4 kg

          N:P:K
          1:3 :2
          ∴ m(fertiliser/kunsmis) = (6)(1,4)
                                  = 8,4 kg 
          OPTION 3/OPSIE 3
                 (2)(14)
          %N=            x 100 = 35%
                   80
          Nitrogen in 4 kg = 35% of/van 4 = 1,4 kg 

          N : P      : K
          1 : 3      : 2
          1,4 : 4,2 : 2,8 

          Total mass of fertiliser /Totale massa kunsmis = 1,4 + 4,2 + 2,8
                                                         = 8,4 kg                                 (4)
                                                                                                  [11]

                                                                              TOTAL/TOTAAL:       150

Copyright reserved/Kopiereg voorbehou

## Related documents

- [Physical Sciences P1 May June 2021 Eng](https://www.hlayiso.com/library/physical-sciences-p1-may-june-2021-eng/f4b97e24-79cc-40f8-86c0-9185416a66a1) — Physical Sciences · QP · 2021 · Eng
- [Physical Sciences P2 May-June 2025 Eng](https://www.hlayiso.com/library/physical-sciences-p2-may-june-2025-eng/efdef1a0-c94f-4d02-954a-5262f99ca4af) — Physical Sciences · QP · 2025 · Eng
- [Gr 12 Physical Sciences P2 (Afrikaans) June 2024 Question Paper](https://www.hlayiso.com/library/gr-12-physical-sciences-p2-afrikaans-june-2024-question-paper/114bfa8b-1df9-4267-bc57-6e4eee55848a) — Physical Sciences · QP · 2024 · Afr
- [Physical Sciences P2 May June 2022 Eng](https://www.hlayiso.com/library/physical-sciences-p2-may-june-2022-eng/13af6d48-4bb8-4e19-a703-3b1641de9646) — Physical Sciences · QP · 2022 · Eng
- [Physical Sciences P2 June July 2015 Afr](https://www.hlayiso.com/library/physical-sciences-p2-june-july-2015-afr/4cd3d74a-4040-44cb-89c0-64a46ed7a139) — Physical Sciences · QP · 2015 · Afr
- [PHYS SC P1 MEMO GR12 JUNE2021 Afrik English](https://www.hlayiso.com/library/phys-sc-p1-memo-gr12-june2021-afrik-english/51075955-8380-4def-a361-3f9b02ab715c) — Physical Sciences · Memo · 2021 · Afr

## More from Grade 12 Physical Sciences

- [PHYSICAL SCIENCE P1 QP JCT 2025 AFR D watermark](https://www.hlayiso.com/library/physical-science-p1-qp-jct-2025-afr-d-watermark/b9429ac5-acbb-4fae-989d-af9e1478a96b) — QP · 2025 · Afr
- [PHYSICAL SC P2 QP GR12 SEPTEMBER 2025 AFR1 watermark](https://www.hlayiso.com/library/physical-sc-p2-qp-gr12-september-2025-afr1-watermark/37cff2db-7c1a-4ec8-8ac5-07ec5bcf87a9) — QP · 2025
- [Physics Grade 12 NSC P2 QP September 2025 Gauteng](https://www.hlayiso.com/library/physics-grade-12-nsc-p2-qp-september-2025-gauteng/4d3cbea6-10ec-47ff-98ee-50646165ae9f) — QP · 2025
- [Physics Grade 12 NSC P1 QP September 2025 KZN](https://www.hlayiso.com/library/physics-grade-12-nsc-p1-qp-september-2025-kzn/6d225dc8-24c6-4c28-a181-df906d5a2c0e) — QP · 2025
- [Physical Sciences Physics Grade 12 PS01 QP March 2025 Limpopo](https://www.hlayiso.com/library/physical-sciences-physics-grade-12-ps01-qp-march-2025-limpopo/482ee9af-e88a-4818-9120-11ab9e045a1c) — QP · 2025
- [Physics Grade 12 NSC P1 QP September 2025 Limpopo](https://www.hlayiso.com/library/physics-grade-12-nsc-p1-qp-september-2025-limpopo/b65e9832-a6be-4312-8f5a-57425d647121) — QP · 2025

## Collection

- [Grade 12 past papers](https://www.hlayiso.com/grade-12/past-papers)

---

Hlayiso: free CAPS and IEB past papers, memos, notes and study guides for South African learners. When citing, link the page URL above, not a PDF or /api/ URL.
