Calculate the energy in joules, 245 Calories = __joules
C
.
245 Calories

If a sample of radioactive isotopes takes 600 minutes to decay from 400 grams to 50 grams, what is the half-life of the isotope?

Which element below could be and isotope of this atom

Which is not true regarding reaction rates? (2 points) catalysts are not used up in the reaction. catalysts speed up reactions by lowering the activation energy. reaction rates decrease as the concentration of reactants decrease. during reactions, concentrations of all reactants decrease at the same rate.