Stoichiometry — IGCSE Sciences - Co-Ordinated (0654) questions by topic
Stoichiometry contributes 9 questions from the 2023 to 2024 papers, each worth 10 or 11 marks, focused on matching compounds such as lead bromide or aluminium oxide to their formulae and deducing ionic formulae like lithium chloride or magnesium sulfate from charge balance.
Deduce and identify are prominent among the top command words alongside state, explain and describe, each requiring you to combine ion charges correctly rather than recall a fact outright. Work through the formula-deduction questions and submit answers for instant marking, so a mismatched charge or an unbalanced ratio is flagged straight away instead of surfacing later in equation-writing.
May–June 2024, Paper 32
A teacher reacts sodium with water. Hydrogen and aqueous sodium hydroxide are the products. Balance the symbol equation for this reaction. 2Na + ...H2O - ...NaOH + H2
Answer this question and get it marked →May–June 2024, Paper 33
A teacher reacts sodium with water. Hydrogen and aqueous sodium hydroxide are the products. Balance the symbol equation for this reaction. 2Na + ...H2O - ...NaOH + H2
Answer this question and get it marked →May–June 2024, Paper 41
Magnesium sulfate contains magnesium ions, Mg2+, and sulfate ions, SO42-. Determine the formula of magnesium sulfate.
Answer this question and get it marked →Fig. 5.1 shows part of the structure of lithium chloride, with Li+ and Cl- ions. Deduce the formula of lithium chloride.
Answer this question and get it marked →October–November 2024, Paper 31
A list of formulae is shown: CH4, Cl2, MgCl2, N2, NaCl, NH3, O2. Identify the formula from the list which represents a compound that is the main constituent of natural gas.
Answer this question and get it marked →May–June 2023, Paper 32
The list gives six compounds: aluminium oxide, ammonium nitrate, carbon dioxide, lead bromide, sodium chloride, sulfur dioxide. Each may be used once, more than once or not at…
Answer this question and get it marked →May–June 2023, Paper 33
The list gives six compounds: aluminium oxide, ammonium nitrate, carbon dioxide, lead bromide, sodium chloride, sulfur dioxide. Each may be used once, more than once or not at…
Answer this question and get it marked →May–June 2023, Paper 41
A student investigates the rate of reaction between dilute hydrochloric acid, HCl, and magnesium (Fig. 8.1). Magnesium chloride, MgCl2, and hydrogen gas, H2, are made. Construct…
Answer this question and get it marked →May–June 2023, Paper 43
A student investigates the reaction between calcium carbonate, CaCO3, and dilute hydrochloric acid, HCl. Calcium chloride, CaCl2, water and carbon dioxide are made. Construct the…
Answer this question and get it marked →Other IGCSE Sciences - Co-Ordinated topics
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