When CINO₂ reacts with NO an equilibrium is established. CINO₂(g) + NO(g) ⇌ NO₂(g) + CINO(g) In each CINO₂ molecule the nitrogen atom is bonded to the chlorine atom and bonded to each of the oxygen atoms separately.

1. (a)Draw a 'dot-and-cross' diagram for the CINO₂ molecule. [2][2]
2. (b)(i)Write the rate equation for this reaction. rate = .......................................................................... [1][1]
3. (b)(ii)Deduce the units of the rate constant, k, when the concentrations of both gases are measured in mol dm⁻³ and the rate is measured in mol dm⁻³s⁻¹. [1][1]
4. (b)(iii)State and explain whether or not the reaction could take place in a single step. [1][1]
5. (c)(i)Draw a graph on the grid to show how the concentration of CINO₂ varies for the first 0.20 seconds. [Figure X.X][2]
6. (c)(ii)Deduce the concentration of the NO₂ product at 0.20 seconds. [1][1]
7. (c)(iii)After 20 seconds the concentration of CINO₂ remains constant. Explain this observation. [1][1]

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