Chemistry 0620/12 February/March 2023: question paper and mark scheme

Question

The arrangements of particles in solids, liquids and gases are different. Which statement about the molecules in ice, water or steam is correct? A The H2O molecules are on average closest together in steam. B The H2O molecules are on average furthest apart in water. C The H2O molecules in steam have the second highest average velocity. D The H2O molecules in ice are able to vibrate.

Question

The melting points and boiling points of three elements, at 1 atm pressure, are shown. melting point boiling point / °C / °C argon –189 –186 nitrogen –210 –196 oxygen –218 –183 Separate samples of argon, nitrogen and oxygen are stored at –200 °C and at 1 atm pressure. How many samples are liquids? A 0 B 1 C 2 D 3

Question

Which statement describes a compound? A It contains two or more elements chemically combined. B It contains two or more elements physically combined. C It contains two or more elements forming an alloy. D It contains two or more elements that can easily be separated.

Question

Which statement about elements in the Periodic Table is correct? A A potassium ion, K+, has the same electronic configuration as a chloride ion, Cl –. B The electronic configuration of a Ca2+ ion is 2,8,8,2. C The halogens are in Group VI and so their atoms have six electrons in their outer shell. D Magnesium is in Period 3 and so a magnesium ion, Mg2+, has three occupied electron shells.

Question

Which statement about ions and ionic bonds is correct? A Bromine atoms form negatively charged bromide ions. B Ionic bonds form between elements in Group VII of the Periodic Table. C Positive ions are formed when atoms lose protons. D Potassium iodide contains negatively charged potassium ions.

Question

Which molecule has only two shared pairs of electrons? A CH4 B Cl 2 C HCl D H2O

Question

Which statement about graphite explains why it is used as an electrode? A It contains ions. B It has a giant covalent structure. C It is a metal. D It has mobile electrons.

Question

Methane, CH4, burns in air to form carbon dioxide and water. What is the balanced equation for this reaction? A CH4(g) + O2(g) → CO2(g) + 2H2O(g) B CH4(g) + 2O2(g) → CO2(g) + 2H2O(g) C CH4(g) + 2O2(g) → CO2(g) + H2O(g) D CH4(g) + 3O2(g) → CO2(g) + 2H2O(g)

Question

Magnesium reacts with steam. Mg + H2O → MgO + H2 When 2.43 g of magnesium reacts with an excess of steam, the products are 4.03 g of magnesium oxide and 0.20 g of hydrogen. What is produced when 7.29 g of magnesium reacts with an excess of steam? A 1.34 g of magnesium oxide and 0.07 g of hydrogen B 4.03 g of magnesium oxide and 0.20 g of hydrogen C 8.06 g of magnesium oxide and 0.40 g of hydrogen D 12.09 g of magnesium oxide and 0.60 g of hydrogen

Question

The diagram shows an electrolysis circuit. At which electrode is hydrogen formed? + – + – A B C D aqueous molten sodium chloride sodium chloride

Question

Which gases are used to generate electricity in a fuel cell? A carbon dioxide and oxygen B hydrogen and methane C hydrogen and oxygen D methane and carbon dioxide

Question

The reaction pathway diagram for a reaction is shown. products energy reactants progress of reaction Which statements about the reaction are correct? 1 The reaction is endothermic. 2 The reaction is exothermic. 3 The diagram represents the combustion of methane. 4 The diagram represents the thermal decomposition of limestone. A 1 and 3 B 1 and 4 C 2 and 3 D 2 and 4

Question

Which row describes a chemical change? new substances there is a are made change of state A always always B always sometimes C never always D never sometimes

Question

Magnesium powder reacts with an excess of dilute hydrochloric acid to produce hydrogen gas. Which statements about this reaction are correct? 1 The smaller the particles of magnesium powder, the more slowly the hydrogen is produced. 2 The higher the temperature, the faster the magnesium powder disappears. 3 The lower the concentration of dilute hydrochloric acid, the faster the rate of reaction. 4 The faster the magnesium powder disappears, the faster the rate of reaction. A 1 and 2 B 2 and 3 C 2 and 4 D 3 and 4

Question

Which statement about hydrated cobalt(II) chloride is correct? A It turns blue when it is heated. B It turns blue when water is added to it. C It turns pink when water is added to it. D It turns white when it is heated.

Question

An aqueous solution reacts with a solid. The products are an alkaline gas, a salt and water. What are the aqueous solution and the solid? aqueous solution solid A sodium hydroxide magnesium carbonate B hydrochloric acid magnesium carbonate C hydrochloric acid ammonium chloride D sodium hydroxide ammonium chloride

Question

Both calcium oxide, CaO, and calcium hydroxide, Ca(OH)2, are used to remove sulfur dioxide, SO2, from flue gases in industrial plants. Which row classifies calcium oxide, calcium hydroxide and sulfur dioxide? calcium oxide calcium hydroxide sulfur dioxide A acidic acidic basic B acidic basic acidic C basic acidic acidic D basic basic acidic

Question

Copper(II) sulfate is prepared by adding excess copper(II) carbonate to sulfuric acid. Why is an excess of copper(II) carbonate added? A to ensure all the copper(II) carbonate has reacted B to ensure all the sulfuric acid has reacted C to increase the rate of reaction D to increase the amount of copper(II) sulfate produced

Question

Part of the Periodic Table is shown. Which element has two electrons in its outer shell and three electron shells? A B C D

Question

Some information about element X is given. ● melting point = 64 °C ● density = 0.86 g / cm3 ● vigorous reaction with water Where in the Periodic Table is X placed? A Group 0 B Group I C Group VII D transition metals

Question

The properties of the element titanium, Ti, can be predicted from its position in the Periodic Table. Which row identifies the properties of titanium? can be conducts forms has used as electricity coloured low density a catalyst when solid compounds A B C D

Question

Which description of brass is correct? A a compound of copper and zinc B a compound of copper and tin C a mixture of copper and zinc D a mixture of copper and tin

Question

What is the symbol of the metal used in the manufacture of aircraft because of its low density? A Al B Cu C Fe D Zn

Question

Which property of stainless steel makes it suitable for making cutlery? A It conducts electricity. B It has a high melting point. C It is resistant to rusting. D It is ductile.

Question

Which substances react to form hydrogen gas? 1 calcium and water 2 silver and dilute hydrochloric acid 3 magnesium and steam 4 zinc and dilute hydrochloric acid A 1, 3 and 4 B 1 and 3 only C 2 and 4 D 4 only

Question

Some statements about the reactions of the metals tin, lithium and manganese are listed. ● Tin does not react with steam but does react with dilute hydrochloric acid. ● Lithium reacts with cold water. ● Manganese does not react with cold water but does react with steam. What is the order of reactivity of the three metals? least most reactive reactive A lithium manganese tin B tin lithium manganese C manganese tin lithium D tin manganese lithium

Question

Which substances are required for iron to rust? A oxygen and salt B oxygen only C water and oxygen D water and salt

Question

Coke (carbon) and limestone are two raw materials used in the extraction of iron from hematite. Which type of reaction occurs when each substance is heated during the process? coke limestone A redox redox B redox thermal decomposition C thermal decomposition redox D thermal decomposition thermal decomposition

Question

Water is treated at a waterworks to make it safe to drink. What is present in the water when it leaves the waterworks? A bacteria and insoluble substances B bacteria only C soluble substances, including chlorine compounds D chlorine compounds only

Question

The formulae of four compounds, W, X, Y and Z, are given. compound formula W FeSO4 X (NH4)3PO4 Y KNO3 Z NaCl Which compounds are mixed to create a fertiliser containing the three elements necessary for improved plant growth? A W and X B W and Z C X and Y D Y and Z

Question

Some combustion reactions produce pollutant gases. Which reactions produce a pollutant gas that is not present in clean air? 1 2CH4 + 3O2 → 2CO + 4H2O 2 2H2 + O2 → 2H2O 3 C + O2 → CO2 4 N2 + O2 → 2NO A 1 and 3 B 1 and 4 C 2 and 3 D 3 and 4

Question

Which row identifies the homologous series to which the molecular structure belongs? molecular structure homologous series H H H H H H A H C C C C C C H alkane H H H H H H H H B H C C H alkene H H H H O C H C C C alcohol H H O H H H H H D H C C C C O H carboxylic acid H H H H

Question

Petroleum is fractionally distilled at an oil refinery. The table shows some fractions and uses. fraction use 1 gasoline fuel for ships 2 refinery gas lubrication 3 naphtha making chemicals 4 kerosene jet fuel Which rows identify a use for the fraction listed? A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 4

Question

What is the word equation for the preparation of ethanol? A glucose → ethanol + carbon dioxide B glucose + yeast → ethanol + water C ethane + water → ethanol D ethene + water → ethanol + carbon dioxide

Question

Which row describes properties of aqueous ethanoic acid? effect of adding effect of adding pH magnesium sodium carbonate A 1 reacts to form reacts to form carbon dioxide hydrogen and water only B 4 reacts to form reacts to form a salt, hydrogen carbon dioxide and water C 5 no reaction reacts to form a salt, carbon dioxide and water D 8 no reaction reacts to form carbon dioxide and water only

Question

Which row describes the relative sizes of monomer and polymer molecules? monomer polymer A large large B large small C small large D small small 37 2.00 g of powdered calcium carbonate is added to 50.0 cm3 of hydrochloric acid. Which apparatus is used to measure these quantities of calcium carbonate and hydrochloric acid? calcium carbonate hydrochloric acid A balance burette B balance thermometer C pipette burette D pipette thermometer

Question

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Question

The diagram shows a chromatogram obtained from the colours of three different sweets, X, Y and Z. red red yellow yellow yellow red red sweet X sweet Y sweet Z How many different red dyes are present in the sweets? A 1 B 2 C 3 D 4

Question

A mixture contains sand and an aqueous solution of sodium chloride. Which processes are used to obtain a sample of solid sand and a sample of solid sodium chloride from the mixture? A crystallisation followed by filtration B evaporation followed by filtration C filtration followed by crystallisation D simple distillation followed by crystallisation

Question

A student tests an unknown compound M. The compound: ● produces a lilac flame using a flame test ● produces a gas which turns limewater cloudy when dilute hydrochloric acid is added. What is M? A sodium sulfate B sodium carbonate C potassium sulfate D potassium carbonate 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 89–103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 actinoids Fr Ra Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og francium radium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium copernicium nihonium flerovium moscovium livermorium tennessine oganesson – – – – – – – – – – – – – – – – – 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.).