Chemistry 0620/12 October/November 2019: question paper and mark scheme

Question

The diagram shows a cup of hot tea. Which row describes the water particles in the air above the cup compared with the water particles in the cup? moving faster closer together A B C D

Question

A student is asked to measure the time taken for 0.4 g of magnesium carbonate to react completely with 25.0 cm3 of dilute hydrochloric acid. Which pieces of apparatus does the student need? A balance, stop-clock, pipette B balance, stop-clock, thermometer C balance, pipette, thermometer D stop-clock, pipette, thermometer

Question

Petroleum is a mixture. Which method is used to separate petroleum? A chromatography B cracking C filtration D fractional distillation

Question

Magnesium hydroxide can be obtained from sea water as shown. calcium reaction sea water containing hydroxide vessel magnesium ions solution separation aqueous stage calcium chloride solid magnesium hydroxide Which process is used in the separation stage to separate solid magnesium hydroxide from the mixture? A crystallisation B filtration C distillation D chromatography

Question

What is the total number of electrons in one molecule of ammonia, NH3? A 6 B 8 C 10 D 11

Question

An isotope of lithium has the symbol 73 Li . What is the arrangement of electrons in one atom of this isotope of lithium? A B C D

Question

Which statement about an alloy is correct? A It is a compound made of two or more elements, one of which is a metal. B It is a layer of a metal plated onto another metal. C It is a mixture of a metal with other elements. D It is a single element.

Question

Graphite is a form of carbon. Why can graphite be used as a lubricant? A Graphite contains unbonded electrons which move through the structure. B Graphite contains weak covalent bonds so the atoms move easily. C Graphite has a low melting point so it easily turns into a liquid. D Graphite has weak attractive forces between layers so they can move.

Question

Magnesium burns in oxygen to form magnesium oxide. The equation for the reaction is shown. 2Mg + O2 → 2MgO Which mass of magnesium oxide is formed when 48 g of magnesium is burned? A 20 g B 40 g C 80 g D 160 g

Question

The apparatus used for electrolysis is shown. power supply electrodes electrolyte Which statement is correct? A Copper forms at the anode in some electrolysis reactions. B Hydrogen forms at the cathode in some electrolysis reactions. C Oxygen forms at the cathode in some electrolysis reactions. D The negative electrode is called the anode.

Question

The temperature of the water in two beakers, X and Y, is measured as 21.5 °C. 5 g of sodium chloride is dissolved in the water in beaker X. The temperature changes to 18.0 °C. 5 g of calcium oxide is dissolved in the water in beaker Y. The temperature changes to 29.4 °C. Which types of process are occurring in beakers X and Y? X Y A endothermic endothermic B endothermic exothermic C exothermic endothermic D exothermic exothermic

Question

Which reaction produces a white-coloured substance? A adding water to anhydrous cobalt(II) chloride B adding water to anhydrous copper(II) sulfate C heating hydrated cobalt(II) chloride D heating hydrated copper(II) sulfate

Question

Four students collect the gas produced from the reaction of calcium carbonate with dilute hydrochloric acid. Each student records the time taken to collect a volume of gas. Which results show the highest average rate of reaction? A 15 cm3 of gas collected in 20 seconds B 50 cm3 of gas collected in 40 seconds C 75 cm3 of gas collected in 80 seconds D 90 cm3 of gas collected in 100 seconds

Question

Which row identifies a chemical and a physical change? chemical change physical change A boiling ethanol burning ethanol B burning ethanol evaporating ethanol C dissolving ethanol in water burning ethanol D evaporating ethanol dissolving ethanol in water

Question

When magnesium is heated with zinc oxide a reaction occurs. The equation is shown. Mg + ZnO → MgO + Zn Which substance is oxidised? A magnesium B magnesium oxide C zinc D zinc oxide

Question

Which statement describes the properties of hydrochloric acid? A Carbon dioxide is produced when limestone reacts with hydrochloric acid. B Hydrogen is produced when sodium hydroxide reacts with hydrochloric acid. C Methyl orange turns yellow in strong hydrochloric acid. D Red litmus paper turns blue when dipped into hydrochloric acid.

Question

A sample of X is heated with aqueous sodium hydroxide and small pieces of aluminium. A gas is produced which turns red litmus paper blue. Aqueous sodium hydroxide solution is added to a second sample of X. A pale green precipitate is observed. What is X? A ammonium nitrate B chromium(II) chloride C iron(II) nitrate D iron(II) sulfate

Question

Which element forms an acidic oxide? A calcium B lithium C magnesium D sulfur

Question

A method used to make copper(II) sulfate crystals is shown. 1 Place dilute sulfuric acid in a beaker. 2 Warm the acid. 3 Add copper(II) oxide until it is in excess. 4 Filter the mixture. 5 Evaporate the filtrate until crystals start to form. 6 Leave the filtrate to cool. What are the purposes of step 3 and step 4? step 3 step 4 A to ensure all of the acid has reacted to obtain solid copper(II) sulfate B to ensure all of the acid has reacted to remove the excess of copper(II) oxide C to speed up the reaction to obtain solid copper(II) sulfate D to speed up the reaction to remove the excess of copper(II) oxide

Question

Which statements describe changes that occur from left to right across a period of the Periodic Table? 1 The atomic number of the elements increases. 2 The metallic character of the elements decreases. 3 The physical state of the elements changes from gas to solid. A 2 only B 1 and 2 only C 1 and 3 only D 2 and 3 only

Question

Which pair of elements reacts together most violently? A chlorine and lithium B chlorine and potassium C iodine and lithium D iodine and potassium

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Which is a typical property of transition elements? A can act as catalysts B poor electrical conductivity C low melting point D low density

Question

Helium is a noble gas. Which statement about helium is correct? A It has eight electrons in its outer shell. B It is a diatomic gas. C It is reactive. D It is used for filling balloons.

Question

Some properties of substance X are listed. ● It conducts electricity when molten. ● It has a high melting point. ● It burns in oxygen and the oxide dissolves in water to give a solution with pH 11. What is X? A a covalent compound B a macromolecule C a metal D an ionic compound

Question

Four unknown metals, Q, R, S and T, are reacted with water, steam and dilute hydrochloric acid. The results are shown in the table. reaction with reaction with reaction with dilute water steam hydrochloric acid Q slow reaction fast reaction fast reaction R no reaction no reaction no reaction S no reaction very slow reaction slow reaction T fast reaction explodes explodes Which statements are correct? 1 R is the least reactive metal. 2 T could be potassium. 3 S is more reactive than Q and R. 4 Metals react faster with steam than they do with water. A 1, 2 and 4 only B 1 and 2 only C 2 and 3 only D 3 and 4 only

Question

What is added to molten iron to make steel? A small amounts of carbon B limestone and coke C calcium oxide and oxygen D hematite and air

Question

Which row describes the uses of aluminium, copper and mild steel? aluminium copper mild steel A aircraft bodies electrical wiring car bodies B car bodies cooking utensils electrical wiring C electrical wiring aircraft bodies food containers D food containers aircraft bodies cooking utensils

Question

River water contains soluble impurities, insoluble impurities and bacteria. River water is made safe to drink by filtration and chlorination. Which statement is correct? A Filtration removes bacteria and insoluble impurities, and chlorination removes soluble impurities. B Filtration removes insoluble impurities, and chlorination kills the bacteria. C Filtration removes soluble and insoluble impurities, and chlorination kills the bacteria. D Filtration removes soluble impurities and bacteria, and chlorination removes insoluble impurities.

Question

Clean, dry air contains nitrogen, oxygen and small amounts of other gases. The noble gases have been left out of the table. Which row shows the composition of clean, dry air? nitrogen / % oxygen / % other gases A 21 78 small amount of carbon dioxide B 21 78 small amount of carbon monoxide C 78 21 small amount of carbon dioxide D 78 21 small amount of carbon monoxide

Question

The apparatus shown is set up and left for a week. damp iron wool air water Which diagram shows the level of the water at the end of the week? A B C D

Question

Farmers add calcium oxide (lime) and ammonium salts to their fields. The compounds are not added at the same time because they react with each other. Which gas is produced in this reaction? A ammonia B carbon dioxide C hydrogen D nitrogen

Question

Which information about carbon dioxide and methane is correct? carbon dioxide methane A formed when vegetation decomposes key B greenhouse gas = true C present in unpolluted air = false D produced during respiration

Question

Which statement about the uses of sulfur dioxide is not correct? A It is used as a bleach in the manufacture of paper. B It is used as a food preservative. C It is used in the manufacture of cement. D It is used in the manufacture of sulfuric acid.

Question

Which statement about limestone and lime is correct? A Limestone combines with water to produce slaked lime. B Lime is obtained from limestone by oxidation. C Lime is used in the desulfurisation of flue gases. D Lime is used in the treatment of alkaline soil.

Question

Some fractions obtained from petroleum are listed. position collected fraction use in the fractionating column 1 gasoline waxes and polishes below refinery gas 2 bitumen making roads above kerosene 3 kerosene jet fuel below gasoline 4 refinery gas heating and cooking above gasoline Which rows are correct? A 1, 3 and 4 B 2, 3 and 4 C 3 and 4 only D 4 only

Question

The structures of three compounds are shown. H H H H H H H C C Br H C Br H C C C Br H H H H H H Which statement explains why these three compounds have similar chemical properties? A They all contain bromine, carbon and hydrogen. B They all contain the same functional group. C They are all carbon-based molecules. D They are all saturated molecules.

Question

Which statement about ethane is correct? A It rapidly decolourises aqueous bromine. B It does not burn. C It forms long-chain compounds called polymers. D It only contains single bonds between its atoms.

Question

Which products are obtained by the cracking of an alkane? alkene hydrogen water A B C D

Question

Which statement about an aqueous solution of ethanoic acid is correct? A It reacts with magnesium to form water as one of the products. B It reacts with sodium carbonate to form carbon dioxide. C It reacts with sodium hydroxide to form hydrogen. D It turns red litmus paper blue.

Question

The diagram shows the structure of a monomer and of the polymer made from it. H H H H n C C C C H H H H n What are the monomer and polymer? monomer polymer A ethane poly(ethane) B ethane poly(ethene) C ethene poly(ethane) D ethene poly(ethene) The Periodic Table of Elements Group I II III IV V VI VII VIII 1 2 H He hydrogen helium Key 1 4 3 4 atomic number 5 6 7 8 9 10 Li Be atomic symbol B C N O F Ne lithium beryllium name boron carbon nitrogen oxygen fluorine neon 7 9 relative atomic mass 11 12 14 16 19 20 11 12 13 14 15 16 17 18 Na Mg Al Si P S Cl Ar sodium magnesium aluminium silicon phosphorus sulfur chlorine argon 23 24 27 28 31 32 35.5 40 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton 39 40 45 48 51 52 55 56 59 59 64 65 70 73 75 79 80 84 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon 16 85 88 89 91 93 96 – 101 103 106 108 112 115 119 122 128 127 131 55 56 57–71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 lanthanoids Cs Ba Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn caesium barium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon 133 137 178 181 184 186 190 192 195 197 201 204 207 209 – – – 87 88 89–103 104 105 106 107 108 109 110 111 112 114 116 actinoids Fr Ra Rf Db Sg Bh Hs Mt Ds Rg Cn Fl Lv francium radium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium copernicium flerovium livermorium – – – – – – – – – – – – – 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 lanthanoids La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu lanthanum cerium praseodymium neodymium promethium samarium europium gadolinium terbium dysprosium holmium erbium thulium ytterbium lutetium 139 140 141 144 – 150 152 157 159 163 165 167 169 173 175 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 actinoids Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr actinium thorium protactinium uranium neptunium plutonium americium curium berkelium californium einsteinium fermium mendelevium nobelium lawrencium – 232 231 238 – – – – – – – – – – – The volume of one mole of any gas is 24 dm3 at room temperature and pressure (r.t.p.).