IGCSE Chemistry 0620/23/M/J/23 , MCQs Effective Solving Strategies

basic science concepts in education like practical exams’ solving strategies, Social links   / khurshid.akhter.562     / akhterhk      / @biochemistryconcepts9991     / hkakhter   [email protected]    • IGCSE Chemistry 0620/21/M/J/23, MCQs Effec...   1 Nitrogen is heated in a balloon, which expands slightly. Which statements about the molecules of nitrogen are correct? 1 They move further apart. 2 They move more quickly. 3 They remain the same distance apart. 4 Their speed remains unchanged. 2 The diagrams represent some elements, compounds and mixtures. 3 Two atoms, X and Y, have the same mass number but different atomic numbers. Which statement about X and Y is correct? A They have the same number of protons. B They have the same number of electrons. C They are in the same group of the Periodic Table. D They have different numbers of neutrons. 4 A sample of pure iron contains three isotopes only. The iron in the sample has a relative atomic mass of 55.9. 5 Magnesium oxide is a white solid at room temperature and pressure. Part of the structure of solid magnesium oxide is shown. 6 In which molecule are all the outer-shell electrons involved in covalent bonding? A Cl 2 B CH4 C HCl D NH3. 7 Which row describes the properties of silicon(IV) oxide? 8 Which row describes the structure of a solid metal and explains the property? 9 What is the formula of potassium oxide? A P2O B PO2 C KO D K2O 10 A dilute aqueous solution of sodium bromide is electrolysed using inert electrodes. Which row identifies the product at the cathode and at the anode? 11 Aluminium is extracted by electrolysis, as shown. Which row shows the ionic half-equations at the cathode and the anode? 12 The reaction pathway diagram for an exothermic reaction is shown. 13 The equation for the complete combustion of ethene is shown. C2H4(g) + 3O2(g)  2CO2(g) + 2H2O(g) What is the overall energy change when one mole of ethene is completely burned? 14 Magnesium reacts with hydrochloric acid to form magnesium chloride and hydrogen. Why does magnesium powder react faster than magnesium ribbon? 15 Which row shows the conditions used in the Contact process? 16 A student heats hydrated copper(II) sulfate. The blue crystals change to a white powder. How can the student reverse this reaction? 17 Which reaction of hydrochloric acid is a redox reaction? 18 Which oxide is amphoteric? 19 Four statements about strong acids are listed. 1 They react with carbonates to form carbon dioxide. 2 They completely dissociate in aqueous solution. 3 They react with ammonium salts to form ammonia. 4 They are proton acceptors. 20 Which reaction mixture will produce a precipitate? 21 Which set of elements shows the change from metallic to non-metallic character across a period of the Periodic Table? 22 A sample of ethanoic acid and a sample of hydrochloric acid have the same concentration. How do the hydrogen ion concentration and pH of ethanoic acid compare to those of hydrochloric acid? 23 What is a typical property of transition elements? 24 Which statement about copper or aluminum is correct? 25 Water from a reservoir flows to the water works where purification process 1 takes place followed by process 2. 26 Calcium reacts with cold water to produce hydrogen. Lead reacts slowly when heated in air to form an oxide but has almost no reaction with steam. Silver does not react with either air or water. Zinc reacts when heated with steam to produce hydrogen. What is the order of reactivity starting with the least reactive? 27 Blocks of magnesium are attached to the bottom of a steel boat to prevent rusting. 28 Which statements about the extraction of iron in a blast furnace are correct? 29 Which statements about water are correct? 30 Oxides of nitrogen form in car engines and are removed by catalytic converters. Which equation represents a reaction that occurs in a catalytic converter? 31 An alkene is represented by the formula CH3CH=CH2. Which name is given to this type of formula? 32 What is the structure of propanoic acid? 33 Butane reacts with chlorine in the presence of ultraviolet radiation. What is the equation for this reaction? 34 A hydrocarbon P is cracked to make compound Q and hydrogen. Compound R is formed by the addition polymerization of compound Q. To which homologous series do P, Q and R belong? 35 Which substances are structural isomers? 36 Ethanol is produced by: 1 the catalytic addition of steam to ethene 2 fermentation. 37 The two monomers shown can be used to form a condensation polymer. 38 Dilute hydrochloric acid is titrated into a conical flask containing sodium hydroxide solution and a few drops of methyl orange indicator. 39 The chromatogram obtained from a chromatography experiment on substance S is shown. 40 Element X burns in air to form an acidic gas that decolourises potassium manganate(VII). What is X?