Nitrosyl chloride, NOCl, can be formed by the reaction between nitrogen monoxide and chlorine, as shown. 2NO + Cl₂ → 2NOCl The initial rate of this reaction is investigated, starting with different concentrations of NO and Cl₂. The results obtained are shown in Table 5.1. Table 5.1 experiment [NO]/mol dm⁻³ [Cl₂]/mol dm⁻³ initial rate/mol dm⁻³ min⁻¹ 1 0.0250 0.0150 3.68 x 10⁻² 2 0.0750 0.0150 3.32 x 10⁻¹ 3 0.0500 0.0600 5.89 x 10⁻¹ Use the data in Table 5.1 to deduce the rate equation for this reaction. Explain your reasoning.

1. (a)(i)Nitrosyl chloride, NOCl, can be formed by the reaction between nitrogen monoxide and chlorine, as shown. 2NO + Cl₂ → 2NOCl The initial rate of this reaction is investigated, starting with different concentrations of NO and Cl₂. The results obtained are shown in Table 5.1. Table 5.1 experiment [NO]/mol dm⁻³ [Cl₂]/mol dm⁻³ initial rate/mol dm⁻³ min⁻¹ 1 0.0250 0.0150 3.68 x 10⁻² 2 0.0750 0.0150 3.32 x 10⁻¹ 3 0.0500 0.0600 5.89 x 10⁻¹ Use the data in Table 5.1 to deduce the rate equation for this reaction. Explain your reasoning.[3]
2. (a)(ii)Use your rate equation from (a)(i) and the data from experiment 1 to calculate the rate constant, k, for this reaction. Include the units of k. k = ................................... units ................................... [2][2]
3. (b)NO₂Cl is another compound containing nitrogen, oxygen and chlorine. In sunlight, NO₂Cl can undergo homolytic fission to release chlorine radicals which can catalyse the conversion of ozone, O₃, into oxygen. Complete the mechanism for this process. initiation (homolytic fission) NO₂Cl → ............................ + ............................ propagation step 1 ............................ + O₃ → ............................ + ............................ propagation step 2 ............................ + ............................ → ............................ + ............................[2]
4. (c)Ozone reacts with nitrogen dioxide, as shown. O₃ + 2NO₂ → N₂O₅ + O₂ The rate of reaction is first order with respect to O₃ and first order with respect to NO₂. Suggest equations for a two-step mechanism for this reaction.[2]