When nitrogen reacts with oxygen under specific conditions, a compound forms.
The percentage composition by mass of this compound is:
N=30.4%O=69.6% \text{N} = 30.4\% \quad \text{O} = 69.6\% N=30.4%O=69.6%Show, by calculation, that the empirical formula of this compound is NO2\text{NO}_2NO2.
The molecular formula of this compound is N2O4\text{N}_2\text{O}_4N2O4. N2O4\text{N}_2\text{O}_4N2O4 is a pale yellow liquid below 21 ∘C21\text{ }^\circ\text{C}21 ∘C. A dynamic equilibrium exists in this liquid, represented by this equation:
N2O4(l)⇌NO+(l)+NO3−(l) \text{N}_2\text{O}_4(\text{l}) \rightleftharpoons \text{NO}^+(\text{l}) + \text{NO}_3^-(\text{l}) N2O4(l)⇌NO+(l)+NO3−(l)When a reaction is in dynamic equilibrium, the forward and backward reactions occur at the same time. State two other features of a reaction that is in dynamic equilibrium.
Suggest why liquid N2O4\text{N}_2\text{O}_4N2O4 conducts electricity, but solid N2O4\text{N}_2\text{O}_4N2O4 does not.
28 exam-style questions on Edexcel IGCSE Chemistry Reversible reactions and equilibria. Each one has a worked solution and a mark scheme showing where the marks go.