Complete the balanced chemical equation for the catalytic decomposition of hydrogen peroxide at room temperature, and fill in the missing state symbols.
………H2O2(aq)→2H2O(……… )+O2(……… ) \dots\dots\dots \text{H}_2\text{O}_2(\text{aq}) \rightarrow 2\text{H}_2\text{O}(\dots\dots\dots) + \text{O}_2(\dots\dots\dots) ………H2O2(aq)→2H2O(………)+O2(………)230 exam-style questions on Edexcel GCSE Chemistry 1.1 Formulae, equations and hazards, covering 1.1.1 Formulae, word and balanced equations, 1.1.2 Balanced ionic equations, and 1.1.3 Hazard symbols and risk in practical work. Each one has a worked solution and a mark scheme showing where the marks go.