A solution is prepared by dissolving 3.05 g of benzoic acid (relative molecular mass 122.0) in 23.0 g of ethanol (relative molecular mass 46.0). What is the mole fraction of benzoic acid in this solution?
4.8×10−24.8 \times 10^{-2}4.8×10−2
5.0×10−25.0 \times 10^{-2}5.0×10−2
1.2×10−11.2 \times 10^{-1}1.2×10−1
9.5×10−19.5 \times 10^{-1}9.5×10−1
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.