Sodium bromate(V) tablets can be used in certain neutralising formulations in hair salons. The mass of sodium bromate(V), NaBrO3\text{NaBrO}_3NaBrO3, in a single tablet can be determined by reacting it with an aqueous solution of sodium bromide, NaBr\text{NaBr}NaBr, in the presence of acid.
BrO3−(aq)+5Br−(aq)+6H+(aq)→3Br2(aq)+3H2O(l) \text{BrO}_3^-(\text{aq}) + 5\text{Br}^-(\text{aq}) + 6\text{H}^+(\text{aq}) \rightarrow 3\text{Br}_2(\text{aq}) + 3\text{H}_2\text{O}(\text{l}) BrO3−(aq)+5Br−(aq)+6H+(aq)→3Br2(aq)+3H2O(l)A quality control chemist finds that two NaBrO3\text{NaBrO}_3NaBrO3 tablets react completely with exactly 45.0 cm345.0\text{ cm}^345.0 cm3 of 0.150 mol dm−30.150\text{ mol dm}^{-3}0.150 mol dm−3 NaBr\text{NaBr}NaBr.
Calculate the mass, in mg, of NaBrO3\text{NaBrO}_3NaBrO3 in one tablet. Use the following relative atomic masses: Na=23.0\text{Na} = 23.0Na=23.0, Br=79.9\text{Br} = 79.9Br=79.9, O=16.0\text{O} = 16.0O=16.0.
Give your answer to the nearest whole number.
199 exam-style questions on OCR A A Level Chemistry Atoms and reactions, covering Atomic structure and isotopes, Compounds, formulae and equations, Amount of substance, Acids, and Redox. Each one has a worked solution and a mark scheme showing where the marks go.