A research chemist prepares a standard non-aqueous electrolyte solution by dissolving 7.5 g of an active organic salt (relative molecular mass 150.0) in 50.4 g of an organic solvent (relative molecular mass 84.0).
What is the mole fraction of the organic salt in this solution?
3.2×10−23.2 \times 10^{-2}3.2×10−2
7.7×10−27.7 \times 10^{-2}7.7×10−2
8.3×10−28.3 \times 10^{-2}8.3×10−2
1.3×10−11.3 \times 10^{-1}1.3×10−1
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.