Question

In the hydrogenation of ethylene using a nickel catalyst, the initial concentration of ethylene is 1.70 M*L-1 and its rate constant (k) is 0.0018 mol*L-1*s-1 . Determine the rate of reaction if it follows a zero-order reaction mechanism.
The rate of reaction turns out to be 0.0018 mol*L-1*s-1

With that in mind, determine the half-life for the reaction using the integrated rate law, given that the initial concentration is 1.70 mol*L-1 and the rate constant is 0.0018 M *L-1*s-1?

Answer 1

Answer:

r = 0.0018 molxL⁻¹xs⁻¹

t = 472.22 s

Explanation:

The rate of the reaction is given by:

$r = k[A]^n$

Where r is the rate, k is the rate constant, [A] is the initial concentration of the reactant and n is the order of the reaction. So, for this problem:

r = 0.0018x[1.70]⁰

r = 0.0018 molxL⁻¹xs⁻¹

The rate is also the variation of the concentration divided by the time. So, for the half-life, the concentration will be decreased by half and will be 0.85 mol/L. So the variation will be 1.70 - 0.85 = 0.85 mol/L. So:

0.0018 = 0.85/t

t = 0.85/0.0018

t = 472.22 s