IGCSE Chemistry (0620) — October–November 2023, Paper 22
40 questions · every question answerable online with instant point-by-point AI marking against the official mark scheme.
Start with Question 1 →Part of a cooling curve for water is shown. 100 temperature / qC X Y time / min What is occurring between points X and Y? A Steam is condensing into water. B The temperature of…
Answer this question and get it marked →Which statements about clean, dry air are correct? 1 It is a mixture of elements only. 2 It is a mixture of elements and compounds. 3 It contains only non-metals. A 1 and 3 B 1…
Answer this question and get it marked →A representation of an atom is shown. – + + – – + + + – – + – What is the nucleon number of this atom? A 6 B 7 C 12 D 13
Answer this question and get it marked →The percentage abundances of three isotopes in a sample of neon are shown. percentage isotope abundance / % 10 Ne 90.48 10 Ne 0.27 10 Ne 9.25 What is the relative atomic mass, Ar,…
Answer this question and get it marked →Potassium reacts with iodine to form potassium iodide. Which statement about potassium iodide is correct? A Each potassium atom shares a pair of electrons with an iodine atom. B…
Answer this question and get it marked →Which substance has the lowest melting point? A graphite B methanol C silicon(IV) oxide D sodium chloride
Answer this question and get it marked →The diagram shows the structure of a molecule of ethyl ethanoate. H O H C C H H H O C C H H H What is the molecular formula of a molecule of ethyl ethanoate? A CHO B C4H8O2 C…
Answer this question and get it marked →A hydrocarbon contains 85.7% of carbon by mass. What is the empirical formula of the hydrocarbon? A CH2 B CH4 C C2H5 D C3H6
Answer this question and get it marked →The formula of a compound containing element X is Na2X2O3. The relative formula mass of the compound is 158. What is the relative atomic mass of X? A 32 B 59.5 C 64 D 119
Answer this question and get it marked →Dilute aqueous potassium chloride is electrolysed using platinum electrodes. Which row identifies the product at each electrode? anode cathode A chlorine hydrogen B chlorine…
Answer this question and get it marked →Concentrated aqueous copper(II) chloride is electrolysed using copper electrodes, as shown. power supply + – copper electrodes aqueous copper(II) chloride What happens to the mass…
Answer this question and get it marked →The initial and final temperatures of four different reactions are measured. Which reaction is the least exothermic? initial final temperature temperature / °C / °C A 19 25 B 21…
Answer this question and get it marked →Which equation represents an endothermic reaction? A Cl 2(g) → 2Cl (g) B CH4(g) + 2O2(g) → CO2(g) + 2H2O(l) C H(g) + H(g) → H2(g) D 2K(s) + 2H2O(l) → 2KOH(aq) + H2(g)
Answer this question and get it marked →Methane burns in oxygen to form carbon dioxide and water. CH4(g) + 2O2(g) → CO2(g) + 2H2O(l) The bond energies are shown. bond energy bond in kJ / mol C–H 410 C–O 360 C=O 805 O–H…
Answer this question and get it marked →Hydrochloric acid is added to excess calcium carbonate in two separate experiments. Two different concentrations of hydrochloric acid are used but the temperature is the same in…
Answer this question and get it marked →The decomposition of dinitrogen tetroxide, N2O4, into nitrogen dioxide, NO2, is a reversible reaction. The equation for the reaction is shown. N2O4(g) 2NO2(g) The forward reaction…
Answer this question and get it marked →In a blast furnace, iron(III) oxide is converted to iron and carbon monoxide is converted to carbon dioxide. Fe2O3 + 3CO → 2Fe + 3CO2 What happens to each of these reactants? A…
Answer this question and get it marked →Which row describes what happens to Fe2+ ions when they are oxidised? oxidation number electron movement of iron A they gain electrons decreases B they gain electrons increases C…
Answer this question and get it marked →In which reaction does an acid react with a base? A Dilute sulfuric acid is added to a piece of magnesium ribbon producing hydrogen. B Dilute sulfuric acid is added to aqueous…
Answer this question and get it marked →Which element forms an oxide that reacts with an aqueous solution of a base? A argon B sulfur C magnesium D copper
Answer this question and get it marked →Which method is used to produce insoluble salts? A addition of excess insoluble base to an acid B addition of excess metal to an acid C precipitation using two aqueous solutions D…
Answer this question and get it marked →The noble gases are in Group VIII of the Periodic Table. Some properties of the first four noble gases are shown. boiling point density noble gas in °C in g / dm3 helium –267…
Answer this question and get it marked →Some properties of element R are shown. melting point in °C 98 boiling point in °C 883 reaction with cold water gives off H2 gas reaction when heated with oxygen burns to give a…
Answer this question and get it marked →Which pair of compounds shows that transition elements have variable oxidation states? A Cr2O3 and CrBr3 B CuSO4 and CuCl 2 C Fe2O3 and FeCl 2 D NiO and NiCl 2
Answer this question and get it marked →The list gives the order of some metals and hydrogen in the reactivity series. Metal X is also included. most reactive K Mg Zn H X least reactive Cu Which row shows the properties…
Answer this question and get it marked →When zinc is added to an aqueous solution containing magnesium ions, there is no reaction. Which species has the greatest tendency to lose electrons? A Mg B Mg2+ C Zn D Zn2+
Answer this question and get it marked →Which gas in the air is needed for iron to rust? A argon B carbon dioxide C nitrogen D oxygen
Answer this question and get it marked →Which coating prevents iron from rusting even when the coating is damaged? A grease B paint C plastic D zinc
Answer this question and get it marked →Why is limestone added to the blast furnace? A It neutralises the molten slag produced. B It reacts with impurities to form slag. C It releases carbon dioxide which reduces the…
Answer this question and get it marked →The flow chart shows stages in the treatment of river water to produce drinking water. river sedimentation stage stage drinking water tank J K water What occurs at stages J and K?…
Answer this question and get it marked →Carbon dioxide acts as a greenhouse gas by interacting with a particular type of energy that radiates from the Earth’s surface into the atmosphere. Which type of energy is…
Answer this question and get it marked →Oxides of nitrogen, such as NO and NO2, are formed in the petrol engines of cars. They are removed from the exhaust gases by reactions in the car’s catalytic converter. Which row…
Answer this question and get it marked →Which diagram shows the displayed formula for the named organic compound? A B C D H O H H H O H H H H C C O O H H C C H H C C H H C C H H H H H H H H ethanoic acid ethene ethanol…
Answer this question and get it marked →What is the total number of covalent bonds in a molecule of butane, C4H10? A 3 B 10 C 13 D 14
Answer this question and get it marked →Propane reacts with chlorine in a substitution reaction. Which reaction condition is required for the reaction to occur? A acid catalyst B iron catalyst C temperature of 400 °C D…
Answer this question and get it marked →The structure of an organic compound is shown. H H H H C C C O H H H H Which structure represents a molecule that reacts with steam to produce this product? A B C D H H H H H H H…
Answer this question and get it marked →Which term describes nylon? A addition polymer B natural polymer C polyamide D polyester
Answer this question and get it marked →Ethene can be polymerised. Which diagram represents the structure of the product formed? A B C D H H H H H H H H H H C C C C C C H C C C C H H H H H n H H n H H H H
Answer this question and get it marked →An acid–base titration is described. ● 25.0 cm3 of dilute aqueous alkali is put into a conical flask. ● Indicator is added to the flask. ● Dilute acid is added to the aqueous…
Answer this question and get it marked →Substance Q is investigated using chromatography. The chromatogram is shown. The diagram is not drawn to scale. solvent front Q 129 mm 114 mm 83 mm baseline 13 mm Q What is the Rf…
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