Ammonium cyanate (NH₄CNO) reacts to form urea (NH₂CONH₂). At 65 $\degree$C, the rate constant, k, is 3.60 L mol¯¹s¯¹. What is the rate law for this reaction?

Question

Quizplus · Accepted Answer

The rate law for a reaction can be determined by experimentally determining the effect of reactant concentration on the rate of the reaction. From the given information, we know that the reaction is first-order with respect to the concentration of ammonium cyanate ([NH₄CNO]) because the rate constant is given as a first-order rate constant (L mol¯¹s¯¹). Therefore, the rate law for the reaction must be Rate = k[NH₄CNO]. However, we also know that ammonium cyanate reacts to form urea, with a stoichiometry of 1:1, so the rate law must be multiplied by the stoichiometric coefficient of ammonium cyanate, giving us Rate = k[NH₄CNO]², which is option B. Note that options A, C, and E have incorrect stoichiometric coefficients or do not include the stoichiometric coefficient at all, while option D includes the correct stoichiometric coefficient but has an incorrect rate constant.

Ammonium Cyanate (NH4CNO) Reacts to Form Urea (NH2CONH2) °\degree° C, the Rate Constant, K, Is 3

Ammonium Cyanate (NH₄CNO) Reacts to Form Urea (NH₂CONH₂) $\degree$ C, the Rate Constant, K, Is 3