The activity of a radioactive sample decreased from` 350 s^-1` to` 175 s^-1` in one hour. Determine the half-life of the species

Before the year 1900 the activity per unit mass of atmospheric carbon due to the presence of 14 C averaged about 0.255Bq per gram of carbon. An archaeological specimen containing 500 mg of carbon, shows 174 decays in one hour. What is the age of the specimen, assuming that its activity per unit mass of carbon when the specimen died was equal to the average value of the air?Half life of ^ 14 C is 5730years?

A car moves in a circle at the constant speed of 50m//s and completes 1 revolution in 40s. Determine the magnitude of acceleration of the car.

A sample of .^32P initially shows activity of one curle.After 303 days the activity falls to 1.5 xx 10^(4) dps.What is the half life of .^32P ?

The half life of a substance in a certain enzyme catalyzed reaction is 138s. The time required for the concentration of the substance to fall from 1.28 mg L^(-1) to 0.04 mg L^(-1) :

The rate constants for a first order reaction are 0.6 s^(-1) at 313 K and 0.045 s^(-1) at 293 K. What is the activation energy?