Question

A certain zero order reaction has rate constant 0.025 M s^-1. What will be the concentration of reactant 'A' after 15 seconds, if initial concentration is 0.50 M?

Options

• 0.50 M

• 0.125 M

• 0.375 M

• 0.060 M

Answer 1

0.125 M

Explanation:

For zero order reaction,

k = `(["A"]_0 - ["A"]_"t")/15`

`therefore 0.025 = (0.50 - ["A"]_"t")/15`

0.375 = 0.50 - [A]_t

∴ [A]_t = 0.50 - 0.375

[A]_t = 0.125 M