A + 2 B + 4 C → products is known to be second order in A, first order in B and independent of the concentration of C. What is the value of the rate constant for this reaction if its rate is 0.783 M · s−1 when [A] = 5.00 M, [B] = 7.00 M, and [C] = 3.00 M? −2 −1 Answerinunitsof M ·s .

4.47 × 10⁻³ M⁻² s⁻¹

Explanation:

Let's consider the following generic equation.

A + 2 B + 4 C → products

This reaction is known to be second order in A, first order in B and independent of the concentration of C (zero order in C). The rate law is:

rate = k × [A]² × [B] × [C]⁰

rate = k × [A]² × [B]

where k is the rate constant

When the rate is 0.783 M/s, [A] = 5.00 M, [B] = 7.00 M, and [C] = 3.00 M, the rate constant is:

k = rate / [A]² × [B]

k = 0.783 M/s / (5.00)² × (7.00) = 4.47 × 10⁻³ M⁻² s⁻¹

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.