Answer:
1.3 s
Explanation:
A first-order reaction can be represented through the following expression.
ln [A] = ln [A]₀ - k.t
where,
[A] is the concentration of the reactant A at a certain time t
k is the rate constant
When the concentration decreases to half its value ([A] = 0.5 [A]₀), the time elapsed is known as half-life t(1/2).
ln (0.5 [A]₀) = ln [A]₀ - k.t(1/2)
ln 0.5 = -k.t(1/2)
t(1/2) = -ln 0.5 / k = - ln 0.5 / (0.54 s⁻¹) = 1.3 s
