A second order reaction of the type A+B>P was carried out in a solution that was initially .075 mol dm-3 in A and .03 mol dm-
3 in B. After 1 hour, the concentration of A had fallen to .02 mol dm-3. a. Calculate the rate constant. b. What is the half life of the reactant? Answers: a. 16.2 dm3mol-hr-, 4.5E-3 dm3mol-s- b. 5.1E3s, 2.1E3 s
31 A dalton is the same as an atomic mass unit. And an atomic mass unit is approximately the mass of a nucleon (proton or neutron) such that the mass is 1 g/mol. So in this problem you have 15 protons and 16 neutrons, so the number of daltons is 15 + 16 = 31.