PHYSICAL SCIENCES PAPER 2 GRADE 10 FISIESE WETENSKAPPE VRAESTEL 2 GRAAD 10 MEMORANDUM TIME / TYD: 3 hours / ure

TOTAL / TOTAAL: 150

Learning Outcomes and Assessment Standards Leeruitkomste en Assesseringsstandaarde LO 1 LO 2 LO 3 AS 10.1.1: Plan and conduct a scientific investigation to collect data systematically with regard to accuracy, reliability and the need to control one variable. Beplan en voer ‘n wetenskaplike ondersoek uit om data sistematies met akkuraatheid, betroubaarheid en die kontrole van een veranderlike, te versamel. AS 10.1.2: Seek patterns and trends in the information collected and link it to existing scientific knowledge to help draw conclusions. Soek patrone en tendense in die versamelde inligting en verbind dit met bestaande wetenskaplike kennis om gevolgtrekkings te maak. AS 10.1.3: Apply given steps in a problemsolving strategy to solve standard exercises. Pas gegewe staape in ‘n probleemoplossingsstrategie toe om standaard oefeninge op te los.

AS 10.2.1: Recall and state basic prescribed scientific knowledge. Herroep en noem basiese voorgeskrewe wetenskaplike kennis. AS 10.2.2 Express and explain prescribed scientific theories and models by indicating some of the relationships of different facts and concepts with each other. Verduidelik en druk voorgeskrewe wetenskaplike teorieë en modelle uit deur van die verwantskappe tussen verskillende feite en konsepte aan te dui. AS 10.2.3: Apply scientific knowledge in familiar, simple contexts. Pas wetenskaplike kennis in bekende eenvoudige kontekste toe.

AS 10.3.1: Discuss knowledge claims by indicating the link between indigenous knowledge systems and scientific knowledge. Bespreek kennisaansprake deur die verband tussen inheemse kennissiteme en wetenskaplike kennis aan te dui. AS 10.3.2: Describe the interrelationship and impact of science and technology on socio-economic and human development. Beskryf die interverwantskap en impak van wetenskap en tegnologie op sosio-ekonomiese en menslike ontwikkeling. AS 10.3.3: Discuss the impact of scientific and technological knowledge on sustainable local development of resources and on the immediate environment. Bespreek die impak van wetenskaplike en tegnolgiese kennis op volhoubare plaaslike ontwikkeling van bronne en op die onmiddellikke omgewing.

SECTION A / AFDELING A QUESTION 1 / VRAAG 1 1.1

Silicon / Silikon ü

[10.2.1]

(1)

1.2

Mass number / Massa nommerü

[10.2.1]

(1)

1.3

Viscosity / Viskositeit ü

[10.2.1]

(1)

1.4

Molecule / Molekuul ü OR compound / verbinding

[10.2.1]

(1)

1.5

Explosion / Ontploffing ü OR exothermic /eksotermies

[10.2.1]

(1) [5]

QUESTION 2 / VRAAG 2 2.1

Cü

[10.2.1]

2.2

Hü

[10.2.1]

(1)

2.3

Eü

[10.2.1]

(1)

2.4

Bü

[10.2.1]

(1)

2.5

Iü

[10.2.1]

(1) [5]

[10.2.1]

(2)

[10.2.3]

(2)

[10.2.1]

(2)

[10.2.3]

(2)

[10.2.1]

(2) [10]

(1)

QUESTION 3 / VRAAG 3 3.1

False. Non-metals are brittle.üü/Metals are ductile. Vals. Niemetale is bros./Metale is smeebaar.

3.2

False. Both isotopes have 10 electrons and not 12 electrons. OR 20 10 Ne has 10 neutrons and not 12 neutrons. üü Vals. Beide isotope het 10 elektrone en nie 12 elektrone nie. OF 20 10 Ne het 10 neutrone en nie 12 neutrone nie.

3.3

False. Only atoms are conserved, molecules decompose to form new compoundsüü Vals. Slegs atome bly behoue, molekule ontbind om nuwe verbindings te vorm.

3.4

True üü Waar

3.5

False. Liquids are incompressible. üü OR There are spaces between particles in liquids. Vals. Vloeistowwe is niesaampersbaar. OF Daar is spasies tussen die deeltjies in ‘n vloeistof.

QUESTION 4 / VRAAG 4 4.1

B üüü

[10.2.1]

4.2

B üüü

[10.2.3]

4.3

A üüü

[10.2.3]

(3)

4.4

C üüü

[10.2.3]

(3)

4.5

C üüü

(3) (3)

(3) [15] Total Section A / Totaal Afdeling A = [35] [10.2.1]

SECTION B / AFDELING B QUESTION 5 / VRAAG 5 5.1

A thermal conductor allows heat energy to flow through it, üwhile an insulator does not allow flow of heat energy. ü ‘n Termiese geleier laat die vloei van hitte toe, terwyl ‘n isolator nie vloei van hitte-energie toelaat nie. [10.2.2]

5.2

(2)

Use the checklist to assess the investigative question. Gebruik die kontrolelys om die ondersoekende vraag te assesseer. Checklist / Kontrolelys Investigative question / Ondersoekende vraag 1 A question that refers to the independent variables. ‘n Vraag wat na die onafhanklike veranderlikes verwys. 2 A question that refers to the dependent variables. ‘n Vraag wat na die afhanklike veranderlikes verwys. Total out of 2 / Totaal uit 2

1

0

Possible investigative questions / Moontlike ondersoekende vrae: Which type of material (towel, newspapers or plastic) shows the smallest decrease in temperature in a given time? Watter tipe materiaal (handdoek, koerante of plastiek) toon die kleinste afname in temperatuur in ‘n gegewe tyd. time? Which type of material (towel, newspapers or plastic) keeps the water warm the longest? Watter tipe materiaal (handdoek, koerante of plastiek) hou die water die langste warm? Which type of material (towel, newspapers or plastic) keeps the heat the best? Watter tipe materiaal (handdoek, koerante of plastiek) behou die hitte die beste?

[10.1.1]

(2)

5.3

Use the checklist to assess the hypothesis. Gebruik die kontrolelys om die hipotese te assesseer. Checklist / Kontrolelys Hypothesis / Hipotese ) 1 The hypothesis is an answer to the investigative question formulated in question 5.2. Die hipotese is ‘n antwoord op die ondersoekende vraag geformuleer in vraag 5.2. 2 The hypothesis refers to all variables. Die hipotese verwys na alle veranderlikes. Total out of 2 / Totaal uit 2

1

0

Possible hypothesis / Moontlike hipotese: Plastic is the best insulator followed by newspaper and then towel. Plastiek is die beste isolator gevolg deur koerantpapier en dan handdoek.

[10.1.1]

(2)

Any two / Enige twee: Thermometer / Termometer üü Watch / Horlosie üü Apparatus to heat water e.g. a kettle. / Apparaat om water te verhit bv.’n ketel

[10.1.1]

(2)

5.5

Types of materials / Tipe materiale üü

[10.1.1]

(2)

5.6

Change in temperature / Verandering in temperatuur ü ü

[10.1.1]

(2)

5.7

Any one / Enige twee: Volume of water / Volume van water üü Time / Tyd üü

[10.1.1]

(4) [16]

5.4

QUESTION 6 / VRAAG 6 6.1

6.2

6.3

The minimum energy necessary üto remove the first electron ü from an atom in the gaseous phase. Die minimum energie benodig om die eerste elektron uit ‘n atoom In die gasfase te verwyder. [10.2.1]

(2)

Ionisation energies increase from left to right in a period. üü Ionisasie-energieë neem toe van links na regs in ‘n periode.

[10.1.2]

(2)

[10.1.2]

(4)

Helium üand neon ü (noble gases) Highest ionization energies. Helium en neon. (edelgasse) Hoogste ionisasie- energieë

6.4

n=1

ü

10Ne

2He

ü

n=2

ü

n=1 [10.2.3]

6.5

6.6

Completely filled energy levels explain stability of He and Ne. Volledig gevulde hoogste energievlakke verduidelik stabiliteit van He en Ne. üü [10.1.2]

(5)

Very stable / unreactive / inert gas. Baie stabiele / onreaktiewe onaktiewe gas. üü

[10.2.2]

(2)

[10.1.2]

(2) [18]

Correct. ü Group I elements have the lowest first ionization energies üand will easily loose electrons to form positive ions. ü Korrek. Groep I elemente het die laagste ionisasie- energieë

QUESTION 7 / VRAAG 7 Needed columns with headings / Nodige kolomme met opskrifte ü Needed rows with names / Nodige rye met name ü

Reactants used Reaktante gebruik Method used Metode gebruik Type of furnace Tipe oond Purity of product Suiwerheid van produk

INDIGENOUS Iron ore, coal ü Ystererts, houtskool Bellows to blow air into furnaces. ü Blaasbalke om blaas lug in oond in te blaas. Clay ovens (furnace) ü Kleioonde Not pure ü Nie suiwer nie.

MODERN Iron ore, coke, limestone ü Ystererts, kooks en kalksteen Hot air blasted into furnace through pipes. ü Warm lug deur pype in die oond ingeblaas. Blast furnace ü Hoogoond Pure ü Suiwer [10.3.1]

[10]

QUESTION 8 / VRAAG 8 8.1

P4 + 5 O2 ü→ 2 P 2O5 ü

[10.2.3]

(2)

(P 2O5 is the empirical formula. Research showed that diphosphorus pentoxide is made up of molecules with formula P4O10 and may be called tetraphosphorus decoxide. For most purposes this is irrelevant and the historical name and formula [P 2O5] have stuck.) 8.2

Mr(P 4) = 4(31) = 124 ü Mr(5 O2) = 5 x (2 x 16) = 160 ü Mr(2 P 2O5) = 2 x (2 x 31 + 5 x 16) = 284 ü Mr(Reactants / Reaktante) = 124 + 160 = 284ü Mr(Products / Produkte) = 284

8.3

8.4

8.5

Total mass before the reaction equals total mass after the reaction and thus mass is conserved. ü Die totale massa van reaktante voor die reaksie is gelyk aan die totale massa van produkte na afloop van die reaksie. [10.1.3; 10.2.3]

(5)

Diphosphorus pentoxide or phosphorus pentoxide. ü ü Difosforpentoksied of fosforpentoksied

[10.2.3]

(2)

Exothermic ü– heat is released. üü Eksotermies – hitte is vrygestel

[10.1.2]

(3)

Synthesis ü– two reactants combine to form one product. ü ü Sintese – twee reaktante verbind om een produk te vorm.

[10.1.2]

(3)

8.6

8.7

No / Nee ü A solid product is formed üand not poisonous or suffocating gases. ‘n Vaste stof vorm en nie giftige of verstikkende gasse nie. ü [10.1.2]

(3)

Humans can get severe burns üüand the environment (vegetation) is damaged due to fires. üü Mense kan ernstige brandwonde opdoen en die omgewing (plantegroei) word beskadig deur vure.

[10.3.2]

(3) [22]

[10.2.3]

(3)

[10.2.3]

(3)

QUESTION 9 / VRAAG 9 9.1

9.2

P1 is evaporation / verdamping ü P2 is condensation/ kondensasie ü Yes. ü It is a cycle. üü (However it does not have to rain at town X all the time.) Ja. Dit is ‘n siklus. (Dit hoef egter nie altyd op dorp X te reën nie.

9.3

Relative humidity may have dropped too low. üü Relatiewe humiditeit kon te lag geval het. Moisture level in the ground may be too low because of high winds. üü Vogvlakke in die grond kan te laag wees as gevolg van sterk winde.

9.4

Deforestration may have taken place or the ecosystem may be disturbed. üü Ontbossing kon plaasgevind het en die ekosisteem kan versteur wees.

[10.3.1]

(6)

Sink a borehole / Sink ‘n boorgat. ü Dig wells / Grawe putte. ü Access aquifers / Verkry toegang tot waterdraers. ü

[10.1.3]

(3) [14]

QUESTION 10 / VRAAG 10 10.1

10.2

Ice is less dense than water. ü Ys is minder dig as water.

(1)

[10.2.3]

(2)

[10.3.3]

(4) [7]

The ice absorbs latentü heat from the water therefore the water cools while the ice gets warm and melts. ü Die ys absorbeer latente warmte uit die water en gevolglik koel die water af, terwyl die ys warm word en smelt.

10.3

[10.2.1]

Ice floats on top of the water and insulates water at the bottom from the cold, üükeeping the temperature of the water high enough to sustain aquatic life. üü Ys dryf bo-op die water en isoleer die water daaronder teen die koue, en hou so die water by ‘n hoë genoeg temperatuur om waterlewe te onderhou.

QUESTION 11 / VRAAG 11 11.1

Urea: Make a solution of the fertiliser and filter the solution üü Ureum: Maak ‘n oplossing van die kunsmis en filtreer die oplossing Ammonium chloride: Heat the solution, evaporate and heat the crystal and condense the sublimate . üü Ammonimchloried: Verhit die oplossing, verdamp en verhit die kristal en kondenseer die sublimaat. Potassium chloride: remains as the residue. üü Kaliumchloried: bly as die residue oor.

11.2

(6)

[10.3.2]

(4)

Improved and fast plant growth üü leading to sufficient food production. üü Verbeterde en vinnige groei van plante wat tot voldoende voedselproduksie lei.

11.3

[10.2.3]

Nitrates are soluble. ü. They can be washed into streams and rivers. ü Hence excessive use of fertilizers causes pollutionüü of water ways. Nitrate is oplosbaar en kan in strome en riviere oplos en waterweë besoedel.

[10.3.3]

(4) [14]

QUESTION 12 / VRAAG 12 12.1

12.2

Global warming / Aardverwarming üü (A result of increased temperature) (‘n Gevolg van ‘n toename in temperatuur.)

[10.3.3]

(2)

[10.3.2]

(4) [6]

X = Potassium carbonate / kaliumkarbonaat üü OR/OF K2CO3 Y = Potassium sulphate / kaliumsulfaat üü OR/OF K2SO4 Z = Potassium chloride / kaliumchloried üü OR/OF KCl

[10.1.3]

(6)

K2CO3 + BaCl 2 ü? BaCO3 + 2KCl ü

[10.2.3]

(2) [8]

Any two / Enige twee: Temperatures will drop and humans may not survive. üü Temperature sal afneem en mense moontlik nie oorleef nie. Some areas may become uninhabitable. üü Sommige areas kan onbewoonbaar raak. Plants may die leading to famine. üü Plante kan doodgaan en sodoende hongesnood veroorsaak.

QUESTION 13 / VRAAG 13 13.1

13.2

Total Section B / Totaal Afdeling B = [115] ______________________________________________________________________ TOTAL OF QUESTION PAPER / TOTAAL VAN VRAESTEL = 150