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Question bank

Original exam-style questions, mapped to your syllabus. Answers are checked for mathematical equivalence and every attempt updates your mastery.

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12 questions

SA-AC-MO-0012 marksL1 FoundationCalculatorThe mole
Calculate the number of molecules in 0.250.25 mol of water. Enter the number.

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Salam Academy Original Practice · Proposed mark scheme
SA-AC-MO-0061 markL1 FoundationCalculatorThe mole
Relative atomic mass is defined relative to
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Salam Academy Original Practice · Proposed mark scheme
SA-AC-MO-0121 markL1 FoundationCalculatorThe mole
The Avogadro constant is
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Salam Academy Original Practice · Proposed mark scheme
SA-AC-MO-0023 marksL2 StandardCalculatorFormulae
A compound contains 40.0% C, 6.7% H and 53.3% O. Its MrM_r is 180. How many carbon atoms are in one molecule?

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Salam Academy Original Practice · Proposed mark scheme
SA-AC-MO-0043 marksL2 StandardCalculatorEquations
4.924.92 g of MgSO4⋅xH2O\mathrm{MgSO_4\cdot xH_2O} is heated to give 2.402.40 g of anhydrous MgSO4\mathrm{MgSO_4} (Mr=120.4M_r=120.4). Find xx.

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Salam Academy Original Practice · Proposed mark scheme
SA-AC-MO-0052 marksL2 StandardCalculatorEquations
Calculate the percentage atom economy for making ethanol by fermentation: C6H12O6→2C2H5OH+2CO2\mathrm{C_6H_{12}O_6\rightarrow2C_2H_5OH+2CO_2} (MrM_r: ethanol 46, CO₂ 44).

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Salam Academy Original Practice · Proposed mark scheme
SA-AC-MO-0071 markL2 StandardCalculatorEquations
The ionic equation for BaCl2(aq)+K2SO4(aq)→BaSO4(s)+2KCl(aq)\mathrm{BaCl_2(aq)+K_2SO_4(aq)\rightarrow BaSO_4(s)+2KCl(aq)} is
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Salam Academy Original Practice · Proposed mark scheme
SA-AC-MO-0082 marksL2 StandardCalculatorThe mole
What mass of Na2CO3\mathrm{Na_2CO_3} (Mr=106M_r=106) contains 0.05000.0500 mol of sodium ions?

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Salam Academy Original Practice · Proposed mark scheme
SA-AC-MO-0091 markL2 StandardCalculatorEquations
A process with 100% atom economy
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Salam Academy Original Practice · Proposed mark scheme
SA-AC-MO-0102 marksL2 StandardCalculatorFormulae
An oxide of nitrogen is 30.4% N by mass. Find the ratio of O atoms to N atoms.

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Salam Academy Original Practice · Proposed mark scheme
SA-AC-MO-0033 marksL3 ExamCalculatorFormulae
0.2900.290 g of a hydrocarbon burns to give 0.8800.880 g CO₂ and 0.4500.450 g H₂O. Find the ratio of H atoms to C atoms in its empirical formula.

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Salam Academy Original Practice · Proposed mark scheme
SA-AC-MO-0113 marksL3 ExamCalculatorFormulae
0.2300.230 g of a compound containing C, H and O burns to give 0.4400.440 g CO₂ and 0.2700.270 g H₂O. How many oxygen atoms are in its empirical formula (with 2 carbons)?

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Salam Academy Original Practice · Proposed mark scheme