The half-life of a first-order reaction can be calculated using the formula t12 = 0.693k
Where t12 = the half-life and k = the rate constant
From the question, we were given the value for k, which is the constant to be 4.5 x 10−3 sec−1
t12 = 0.693k = 0.6934.5x10(−3}\)
t12 = 154 s
