Critical mass is the smallest amount of certain element of mass that is needed to achieve a nuclear chain reaction early . Since Pu - 239 releases an average of 2.7 neutrons per fission as compared to U - 235 that releases 2.5 neutrons per fission. So, Pu - 239 has smaller critical mass, because Pu - 239 has a higher probability for fission and produces a large no. of neutrons per fission event. Infact of all the basic nuclear fuels, Pu - 239 has smallest critical mass. Critical mass depends on the nuclear properties of elements undergoing fission reaction. Hence, as Pu - 239 produces large no. of neutrons per fission than U - 235 and Pu - 239 has smaller critical mass.
THAT LINK IS A VIRUS NEVER GO TO A LINK and if you go to “goggle” you should see a camera icon and take a picture of the question and get the answer there
1. they were both educated in france 2. they both felt that the end of the monarchy was inevitable 3. they were both artist 4. they both felt that science would improve the world
