The compound nitrosyl bromide, NOBr, can be formed by the reaction shown. 2NO + Br₂ ⇌ 2NOBr (c) The rate of the reaction was measured at various concentrations of the two reactants, NO and Br₂, and the following results were obtained. experiment | [NO]/mol dm⁻³ | [Br₂]/mol dm⁻³ | initial rate /mol dm⁻³s⁻¹ ---|---|---|--- 1 | 0.03 | 0.02 | 3.4 x 10⁻³ 2 | 0.03 | 0.04 | 6.8 x 10⁻³ 3 | 0.09 | 0.04 | 6.1 x 10⁻² 4 | 0.12 | 0.06 | to be calculated The general form of the rate equation for this reaction is as follows. rate = k[NO]ᵃ[Br₂]ᵇ (d) The reaction between X and Y was studied. 2X + Y → Z The following sequence of steps is a proposed mechanism for the reaction. step 1 step 2 2X → V V + Y → Z The general form of the rate equation for this reaction is as follows. rate = k[X]ᵐ[Y]ⁿ Step 1 is the slower step in the mechanism.