For the reversible, one-step reaction A+B<>C+D, the forward rate constant is 52.4 /mol*h and the rate constant for the reverse reaction is 32.1 L/mol*h. The activation energy was found to be 35.2 kJ/mol for the forward reaction and 44.0 kJ. mol for the reverse reaction.

a) What is the equilibrium constant for the reaction?

b) is the reaction exothermic or endothermic?

c) What will be the effect of raising the temperature on the rate constants and the equilibrium constant?

catya your not at all which answer i've seen you do this on another question!

it is the minimum amount of material needed to sustain a fission reaction.

critical mass is the minimum amount of fissionable material that must be assembled for a sustained fission reaction to take place. although two to three neutrons are produced for every fission, not all of these neutrons are available for continuing the fission reaction. if the conditions are such that the neutrons are lost at a faster rate than they are formed by fission, the chain reaction will not be self-sustaining.   at the point where the chain reaction can become self-sustaining, this is referred to as critical mass.