This question is about magnesium sulfate (Epsom salt).
When crystalline hydrated magnesium sulfate is heated, it loses water of crystallisation to form a white anhydrous powder. The word equation for this reaction is:
hydrated magnesium sulfate (crystalline)⇌anhydrous magnesium sulfate (powder)+water \text{hydrated magnesium sulfate (crystalline)} \rightleftharpoons \text{anhydrous magnesium sulfate (powder)} + \text{water} hydrated magnesium sulfate (crystalline)⇌anhydrous magnesium sulfate (powder)+waterWhat does the symbol ⇌\rightleftharpoons⇌ represent?
A student heats 6.0 g6.0\text{ g}6.0 g of hydrated magnesium sulfate in a crucible. After heating to constant mass, 3.06 g3.06\text{ g}3.06 g of water vapour has been released into the atmosphere.
Calculate the mass of anhydrous magnesium sulfate remaining in the crucible.
Calculate the percentage by mass of water in the original 6.0 g6.0\text{ g}6.0 g sample of hydrated magnesium sulfate.
21 exam-style questions on AQA GCSE Chemistry 6.2 Reversible reactions and dynamic equilibrium, covering 6.2.1 Reversible reactions, 6.2.2 Energy changes and reversible reactions, 6.2.3 Equilibrium, 6.2.4 The effect of changing conditions on equilibrium (HT only), 6.2.5 The effect of changing concentration (HT only), 6.2.6 The effect of temperature changes on equilibrium (HT only), and 6.2.7 The effect of pressure changes on equilibrium (HT only). Each one has a worked solution and a mark scheme showing where the marks go.