Physical Sciences Grade 12 Paper 2 Free State June 2025 Memo

education Department of Education FREE STATE PROVINCE GRADE 12 / GRAAD 12 PHYSICAL SCIENCES / FISIESE WETENSKAPPE JUNE / JUNIE 2025 MARKS / PUNTE: 150 MARKING GUIDELINES / MERKRIGLYNE. This MEMO consists of 12 pages. / Hierdie MEMO bestaan uit 12 bladsye. Copyright reserved/Kopiereg voorbehou Please turn over/Blaai asseblief om

QUESTION /VRAAG 1 1414. Cvv 12 Avv 13° Cvv 14 Dvv 15 Bvv 16 Dvv 17 Bvv 18 Dvv 19 Bvv 1.10 Dvv Copyright reserved/Kopiereg voorbehou FS June/VS Junie 2025 (2) (2) (2) (2) (2) (2) (2) (2) (2) (2) [20] Please turn over/Blaai asseblief om

FS June/VS Junie 2025 QUESTION 2/ VRAAG 2 2.1.1 Organic compounds that consist of hydrogen and carbon atoms only YY (2) Organiese verbindings wat slegs uit waterstof- en koolstofatome bestaan 2.1.2 CaHoneo ¥ (1) 2.1.3. 2,2,5-trimethylheptane 2,2,5-trimetielheptaan Criteria/ Kriteria Marks/ Punte Heptane/heptaan v trimethyl/trimetiel v Correct numbers, commas and hyphens/ vi Korrekte getalle, kommas en koppeltekens (3) 2.2.1 Aldehyde ~ (1) Aldehied 2.2.2 CH3COCHs Yv/ song io, (2) Criteria/ Kriteria Marks/Punte Functional group/ Funksionele groep v Whole structure correct/ Hele struktuur korrek v 2.2.3. Propanone vv accept: Propan-2-one / 2-Propanone (2/0) (2) Propanoon —aanvaar: Propaan-2-00n / 2-Propanoon 2.3.1 Simplest whole number ratio in which atoms combine ina compoundYvY (2) Eenvoudigste heelgetalverhouding waarin atome in ‘n verbinding verbind 232 Mol offvan C [ Mol offvan H | _ Mol of/van O i 5882, . 9.81, ; 31.37 | 12 1 16 4,90 : 9,81 : 1,96 2,5 t 5 i 1 x2v C 5 : 10 ; 2 | Molecular formula/Molekulére formule : CsHi9O2 (5) 2.3.3. POSITIVE MARKING FROM QUESTION 2.3.2/POSITIEF NASIEN VANAF VRAAG 2.3.2 C2HsOH ¥ v / C2HeO (2) [20] Copyright reserved/Kopiereg voorbehou Please turn over/Blaai asseblief om

FS June/VS Junie 2025 QUESTION 3/ VRAAG 3 3.1. The pressure exerted by a vapour at equilibrium with its liquid in closed system.v ¥ (2) Die druk wat deur 'n damp in ewewig met sy vioeistof in 'n geslote sisteem uitgeoefen word 3.2 Criteria/ Kriteria Marks/ Punte Dependent and independent variables correctly identified v (intermolecular force/functional group & vapour pressure)/ Afhanklike en onafhanklike veranderlikes korrek geidentifiseer (intermolekulére_krag/funksionele groep en dampdruk) There is a relationship between independent and dependent v variable/ Daar is 'n verband tussen onafhanklike en afhanklike veranderlike If: e No question mark indicated at the end of the investigative question, then penalise ONE mark. Max. 1/2 e Temperature is identified as one of the variables, then both marks are forfeited. Max. 0/2 Indien: e Geen vraagteken word aan die einde van die ondersoekende vraag aangedui nie, dan word EEN punt gepenaliseer. e Temperatuur word as een van die veranderlikes geidentifiseer, dan word beide punte verbeur. What is the effect of changing intermolecular force on vapour pressure? V ¥ Wat is die effek van die verandering van intermolekulére krag op dampdruk? OR What is the relationship between the intermolecular force and vapour pressure? (2) Wat is die verband tussen die intermolekulére krag en dampdruk? 3.3. 68°C vv (Range/ Variansie (67°C - 69°C) (2) 3.4 Yv; because the vapour pressure of W is higher than that of Y.v v /boiling point of W is lower than the boiling point of Y.v” OR vapour pressure of Y is lower than that of W./ boiling point of Y is higher than the boiling point of W. Y ; Die dampdruk van Wis hoér as die van Y. / dus is die kookpunt van W laer as die van Y. OF Die dampdruk van Y is laer as die van W. / dus is die kookpunt van Y hoér as die van W. (3) 3.5 Carboxyl (group)v ¥ (2) Karboksiel (groep) Copyright reserved/Kopiereg voorbehou Please turn over/Blaai asseblief om

3.6 FS June/VS Junie 2025 X/aldehyde (in addition to London forces dispersion forces) has dipole-dipole forcesY¥ Y/alcohol (in addition to London forces dispersion forces, dipole-dipole forces has one site) of hydrogen bondingY Hydrogen bonding in Y/alcohol are stronger than dipole-dipole forces in X/aldehyde ¥ OR Intermolecular forces in Y/alcohol are stronger than the intermolecular forces in X/aldehyde More energy is required to overcome the intermolecular force in Y/alcohol than in X/aldehydes¥ X/aldehied (benewens die dispersiekragte van Londense kragte) het dipoo!-dipoot kragte Y/alkoho! (benewens Londense kragte se verspreidingskragte, dipoo!-dipoolkragte het een plek) van waterstofbinding Waterstofbindings in Y/alkohol is sterker as dipool-dipoolbindings kragte in X/aldehied OF Intermolekulére kragte in Y/alkohol is sterker as die intermolekulére kragte in X/aldehied Meer energie word benodig om die intermolekulére krag in Y/alkohol as in X/aldehiede te oorkom. OR/OF X/aldehyde in addition to London forces/dispersion forces has dipole-dipole forcesY Y/alcohol (in addition to London forces/dispersion forces/dipole-dipole forces has one site) of hydrogen bondingY X/aldehyde has dipole-dipole forces which are weaker than hydrogen bonding in Y/alcohol¥ OR Intermolecular forces in Y/alcohol are stronger than the intermolecular forces in X/aldehyde More energy is required to overcome the intermolecular force in Y/alcohol than in X/aldehydesY X/aldehied benewens Londense kragte/dispersiekragte het dipool-dipool kragte “ Y/alkohol (benewens Londense kragte/dispersiekragte/dipool- dipoolkragte het een plek) van waterstofbinding ~ X/aldehied het dipool-dipoolkragte wat swakker is as waterstofbinding in Y/alkohol ~ OF Intermolekulére kragte in Y/alkohol is sterker as die intermolekulére kragte in X/aldehied Meer energie word benodig om die intermolekulére krag in Y/alkohol as in X/aldehiede te oorkom. “ (4) Copyright reserved/Kopiereg voorbehou Please turn over/Blaai asseblief om

FS June/VS Junie 2025 BA Criteria/ Kriteria Marks/Punte | Functional group/ Funksionele groep v Whole structure correct/ Hele struktuur korrek v | v H\ 9\H (2) nd bw Hy a H—C—H i 3.7.2. Tertiary alcohol”, the carbon atom bonded to the hydroxyl group is bonded to three other carbon atomsY (2) Tersiére alkohol, die koolstofatoom gebind aan die hidroksielgroep is gebind aan drie ander koolstofatome [19] Copyright reserved/Kopiereg voorbehou Please turn over/Blaai asseblief om

FS June/VS Junie 2025 QUESTION 4/ VRAAG 4 4.1.1 Saturated v It contains carbon-to-carbon single bonds only.” (2) Versadig Dit bevat slegs koolstof-tot-koolstofbindings, enkelbindings. 4.1.2 Hydrogen bromide “ Waterstofbromied (1) Li Ltt rr oe a ee on i iis cin head hon a CRITERIA! KRITERIA “TY “Marks/— Punte Correct structure of organic reactant/ Korrekte struktuur van | ¥ organiese reaktant Correct functional group of organic product/ Korrekte v funksionele groep van organiese produk Whole structure organic product is correct / Hele struktuur v organiese produk is korrek Correct structure of the inorganic product/ Korrekte struktuur | ¥ van die anorganiese produk Accept HBr/ Aanvaar HBr If condensed structures are used/ Indien gekondenseerde Ya strukture gebruik word max/maks (4) 4.2.1 Combustion/Oxidation (reaction) “ Verbranding/Oksidasie (reaksie) (1) 4.2.2 CsHi2 + 802 ¥— 5CO2 + 6H20 Y (bal) ¥ (3) 4.3.1 High pressure Y Hoé druk (1) 4.3.2 CHsCH2CH2CH2CH2CH3 ¥Y > 3CH2CH2Y + H2Y (3) (Give 2/3 if structural formulae are used/Gee 2/3 indien strukturele formules gebruik word) 4.3.3. Addition/Hydrogenation “/ Addisie/Hidrogenering CaHe ¥ (2) 4.4.1 Elimination/dehydrohalogenation v’/ Eliminasie/dehidrohalogenering (1) 4.4.2 Concentrated “/ Gekonsentreerd (1) 443 CRITERIA KRITERIA Marks/ A. H H Punte Correct functional group/ v H—C—C=C—C—-H Korrekte funksionele groep | | I | Whole structure correct/ Hele | ¥ H H HH struktuur korrek (2) [21] Copyright reserved/Kopiereg voorbehou Please turn over/Blaai asseblief om

FS June/VS Junie 2025 QUESTION 5/ VRAAG 5 5.1. Change in concentration of reactants or products per unit time.v “ (2) Verandering in konsentrasie van reaktante of produkte per tydseenheid. Accept/Aanvaar Rate of change in concentration/Tempo van verandering in konsentrasie 5.2 No,” more than one independent variable v (2) Nee, meer as een onafhanklike veranderlike 5.3.1 Reaction rate v/ Reaksietempo (1) 5.3.2 Concentration (of the acid)”’/ Konsentrasie (van die suur) (1) Accept/Aanvaar: Mass of Mg/ Massa van Mg 5.4 Cwill have a higher reaction rate v/ C sal 'n hoér reaksietempo hé e HC2 concentration in experiment A is less than in experiment C ¥ e Less particle available to react in experiment A than in experiment C per unit volume (according to c = - ).% e Less particles with correct orientation/sufficient kinetic energy in experiment A than in experiment C. v e Less effective collision per unit time in experiment A. Vv e¢ HCé konsentrasie in eksperiment A is minder as in eksperiment C e Minder deeltjie beskikbaar om in eksperiment A te reageer as in eksperiment C per eenheidsvolume (volgens c =) e Minder deeltjies met korrekte oriéntasie/voldoende kinetiese energie in eksperiment A as in eksperiment C. e Minder effektiewe botsing per tydseenheid in eksperiment A. OR /OF e HC2 concentration in experiment C is greater than in experiment A. e More particle available to react in experiment C than in experiment A per unit volume (according to c = = ). e More particles with correct orientation/sufficient kinetic energy in experiment C than in experiment A. e More effective collision per unit time in experiment C. e HC konsentrasie in eksperiment C is groter as in eksperiment A. e Meer deeltjie beskikbaar om in eksperiment C te reageer as in eksperimen A per eenheidsvolume (volgens c = =). e Meer deeltjies met korrekte oriéntasie/voldoende kinetiese energie in eksperiment C as in eksperiment A. e Meer effektiewe botsing per tydseenheid in eksperiment C. (5) Copyright reserved/Kopiereg voorbehou Please turn over/Blaai asseblief om

FS June/VS Junie 2025 5.6 _m Niv)= iy sie tt 24 = 0,208 mol Mol ratio/ Molverhouding Mg: HC£ 1: 2v N(HC2):eacted/gereageer =0,415 | n =v ey 0,9= ae "0,5 n(HCe) initiavaanvanklike = 0,45 mol n (HC£) unreacted/oormaat = 0,45 — 0,415v = 0,035 mol ¥ (6) Range/ Reeks: (0,033 — 0,037) 5.6.1 Cav HCtis in excess “/ HC? is in oormaat (2) 5.6.2 Nature of the reacting substance v/ Aard van die reagerende stof (1) 563 BY (1) 5.6.4 Number of moles of Mg reacting with HC? is greater than number of moles of Ca reacting with HCE vv (2) Aantal mol Mg wat reageer met HC¢f is groter as die aantal mol van Ca wat met HC? reageer 5.7 Cav (1) 5.8 Reactivity increases down the group ¥ Reaktiwiteit neem toe afwaarts in die groep (1) [25] Copyright reserved/Kopiereg voorbehou Please turn over/Blaai asseblief om

FS June/VS Junie 2025 QUESTIONG / VRAAG 6 6.1 6.2.1 62:2 6.2.3 6.3.1 6.3.2 When the equilibrium of an isolated system is disturbed, the system will reinstate the new equilibrium by favouring the reaction that opposes disturbance. v ¥ (2) Wanneer die ewewig van 'n geisoleerde sisteem versteur word, sal die sisteem die nuwe ewewig herstel deur die reaksie wat die versteuring teenstaan, te bevoordeel. Increases V/ Verhoog (1) Increases V/ Verhoog (1) System will decrease CQz2(g) by favouring the reaction that uses up CO2(g).v Forward reaction favoured.v Thus causes an increase in the yield of CO. (2) Stelsel sal CO2(g) verminder deur die reaksie wat opgebruik, te bevoordeel. CO2g). Voorwaartse reaksie bevoordeel. Dus veroorsaak dit 'n toename in die opbrengs van CO. Increases “7 Verhoog e Anincrease in pressure favours the reaction which produces the least number of gas moles.” e The reverse reaction is favoured. v (3) e 'n Toename in druk bevoordeel die reaksie wat die minste aantal gasmol. e Die omgekeerde reaksie word bevoordeel. No effect” Temperature is the only factor affecting Kc value (1) Geen effek nie, Temperatuur is die enigste faktor wat die Kc-waarde beinvioed [10] Copyright reserved/Kopiereg voorbehou Please turn over/Blaai asseblief om

FS June/VS Junie 2025 QUESTION 7 7.1.1. Asystem that is isolated to its surroundings/ A system where substances cannot leave/escape the container.v “ (2) 'n Sisteem wat van sy omgewing geisoleer is/'n Sisteem waar stowwe nie die houer kan verlaat/ontsnap nie. 7.1.2 Rate of the forward reaction is equal to the rate of the reverse reaction.v Y (2) Die tempo van die voorwaartse reaksie is gelyk aan die tempo van die terugwaartse reaksie 7.2 Chemical equilibrium.“ Chemiese ewewig. (1) 7.3 Using moles [Y2] = Marking criteria Gebruik van molle Merkkriteria 0,2197 Vv= Divide the equilibrium moles by 2 dmv Correct Ke expression.” Substitution of Ke of 0,2197 value correctly.” The correct value of X2 concentration. Correct substitution of values on the numerator. Deel die ewewigsmolle deur 2 dm? Korrekte Ke uitdrukking. Korrekte vervanging van Ke van 0,2197 waarde. Die korrekte waarde van X2 konsentrasie. Korrekte vervanging van waardes op die teller. [X2][¥2]* (0,25)? “ 10.411Y2]5 ¥ 0,89 mol-dm? ¥ (5) Copyright reserved/Kopiereg voorbehou Please turn over/Blaai asseblief om

FS June/VS Junie 2025 7.4 POSITIVE MARKING FROM QUESTION 7.3/POSITIEF NASIEN VANAF VRAAG 7.3. Marking criteria: * n(¥2) equilibrium x 2 dm*. ¥ moles of Y2.¥ e Formula n(Y2)= mY e Final answer.v Merkkriteria: © n(¥2) ewewig x 2dmo.v om gereageerde mol Y2 te vind.v « Aanvanklike molle(n(Y¥2) ewewig + n(¥2)verander/gereageer).” « Formulen (Y¥2)= mY « Finale antwoord. ¥ * Correct use of mole ratio between Y2: XY3 - 3:2 to find reacted e Initial moles (n(Y2) equilibrium + n(Y2)change/reacted).v ¢ Correct substitution into n(Y2)initial= av * Korrekte gebruik van molverhouding tussenY2:XY3- 3:2 * Korrekte vervanging in n(Y2)initial= am” Xe Y2 XY3 Initial/Aanvanklik (mol) 1,05 2,53V 0 ee Change/Verandering (mol) 0,25 0,75 0,5” Equilibrium/Ewewig (mol) 0.8 1,784 0,5 Equilibrium concentration/ 0,4 0,89 0,25 Ewewigskonsentrasie c == ( mol-drv’) Vv NY )* iv 2 sie we 24 V = 56,67 dm’ v Range/ Reeks: (56,5 — 56,8) 7.5 Increase in temperature.” (6) e Increase in temperature favours the endothermic reactionY Reverse reaction is favoured.” e The numbers of mole XY3 decreases and the number of moles of X2and Y2 increases. ¥ Toename in temperatuur. (4) e Toename in temperatuur bevoordeel die endotermiese reaksie. e Omgekeerde reaksie word bevoordeel. e Die aantal mol XY3 neem af en die aantal mol X2 en Y2 neem toe. Copyright reserved/Kopiereg voorbehou [20] Please turn over/Blaai asseblief om

FS June/VS Junie 2025 QUESTION 8/ VRAAG 8 8.1.1 Activation energy v/Aktiveringenergie (1) 8.1.2 Shifts to the leftv It provides an alternative pathway of lower activation energyY (2) Skuif na links Dit bied 'n alternatiewe pad van laer aktiveringsenergie 8.1.3 (a) (curve/kromme) 3 ¥ (1) (b) = (curve/kromme) 1 ~ (1) 8.2.1 Exothermic v, AH is less than zero/energy of the reactants is more than the energy of the products “ (2) Eksotermies, 4H is minder as nul/energie van die reaktante is meer as die energie van die produkte 8.2.2 Remains the same “/ Bly dieselfde (1) 8.2.3 AH =Hp—Hr —150 ¥ = Hp — 100 ¥ Hp = -50 kJ.mol!¥ (3) 8.2.4 Eac=Eat+ Hr =90 + 100 ¥ = 190 kJ.mot'” (2) 8.2.5 f 2 aa BP iy % Po Bg \ 2 = |Reactants//’ i; UW @ 2 |Reaktante \ Za2 roducts/ Produkte on = 22o~ oo ag . Course of reaction/ Verloop van reaksie CRITERIA /KRITERIA Energy of products and reactants stays the same/ vi Energie van produkte en reaktante bly dieselfde Lower activation energy for the catalysed reaction/ v (2) _Laer aktiveringsenergie vir die gekataliseerde reaksie [15] GRAND TOTAL GROOTTOTAAL: 150 Copyright reserved