When heated, a sample of potassium chlorate(V) (KClO3\text{KClO}_3KClO3) produced 85.0 cm3 of oxygen, measured at 315 K and 102 kPa.
2KClO3(s)→2KCl(s)+3O2(g) 2\text{KClO}_3(\text{s}) \rightarrow 2\text{KCl}(\text{s}) + 3\text{O}_2(\text{g}) 2KClO3(s)→2KCl(s)+3O2(g)What is the amount, in moles, of potassium chlorate(V) that has decomposed?
The gas constant, R=8.31 J K−1 mol−1R = 8.31\text{ J K}^{-1}\text{ mol}^{-1}R=8.31 J K−1 mol−1
1.66×10−31.66 \times 10^{-3}1.66×10−3
2.21×10−32.21 \times 10^{-3}2.21×10−3
3.31×10−33.31 \times 10^{-3}3.31×10−3
4.97×10−34.97 \times 10^{-3}4.97×10−3
79 exam-style questions on AQA A Level Chemistry Amount of substance, covering Relative atomic mass and relative molecular mass, The mole and the Avogadro constant, The ideal gas equation, Empirical and molecular formula, and Balanced equations and associated calculations. Each one has a worked solution and a mark scheme showing where the marks go.