Dinitrogen pentoxide (N2O5) decomposes

Question

by first-order kinetics with a rate constant of
0.0064 s−1
at a certain temperature. What is
the half life for the decomposition of N2O5 at
this temperature?
Answer in units of s.

i did: ln(.003135/x)=(5/8.314)((1/300)-(1/487))

i got .00311 but its wrong

Answer 1

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