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

Question

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The rate law for this reaction is determined by the experimentally measured rate constant and the concentrations of the reactants. From the given information, we know that the rate constant (k) is 3.60 L mol^-1 s^-1. The reaction involves only one reactant, ammonium cyanate (NH₄CNO), which means that the rate law must only involve this reactant. The rate law for the reaction can be expressed as: Rate = k [NH₄CNO]^x where x is the order of the reaction with respect to NH₄CNO. To determine x, we need to run the reaction at different concentrations of NH₄CNO and measure the corresponding rates. Since x cannot be determined from the given information, we should look at the answer choices to see which one(s) make sense. Choice B is the best choice because it includes NH₄CNO raised to a power of 2 (²), which suggests that the reaction is second order with respect to NH₄CNO. This makes sense because the product, urea, contains two NH₄CNO molecules. Choice A is incorrect because it only includes NH₄CNO without any indication of the order of the reaction. Choice C is incorrect because it includes a concentration unit of mol L^-1, which is not consistent with the units of the rate constant (L mol^-1 s^-1). Choice D is incorrect because it includes both NH₄CNO and urea, which is not appropriate for a rate law that only involves one reactant. Choice E is incorrect because it includes urea, which is a product and not a reactant.

Ammonium Cyanate (NH4CNO) Reacts to Form Urea (NH2CONH2)

Ammonium Cyanate (NH₄CNO) Reacts to Form Urea (NH₂CONH₂)