Nuclear decay occurs according to first-order kinetics. cobalt-60 decays with a rate constant of 0.131 years−1. after 5.00 years, a sample has a mass of 0.302 g. what was the original mass of the sample?

Answer : The original mass of the sample was 0.581 grams.

Explanation :

Expression for rate law for first order kinetics is given by:

where,

k = rate constant  =

t = time passed by the sample = 5.00 years

a = original or initial amount of the reactant  = ?

a - x = amount left after decay process = 0.302 g

Now put all the given values in above equation, we get

Therefore, the original mass of the sample was 0.581 grams.

i think the answer would be reserve.

we're given that v₀ = 0 and a = 5.4 m/s². therefore, since v = at + v₀ for constant acceleration the equation for velocity is

after 28s,

m/s

which i would round to 150 m/s as my final answer