chemistry
posted by Jin .
A reaction has a first order rate constant of (6.25x10^5 1/s) at T=298.15K and (0.0000538 1/s) at T=338.15K.
What is the value of the rate constant at T=316.15K?

Use the Arrhenius equation. Substitute k1 and k2 rates at the appropriate T and solve for Ea (activation energy); then use the same equation with Ea you found to solve for the new k.