Alpha decay is one process that unstable atoms can use to become more stable. During alpha decay, an atom's nucleus sheds two protons and two neutrons in a packet that scientists call an alpha particle. Since an atom loses two protons during alpha decay, it changes from one element to another.
Answer:
Pu - 239 have the smaller critical mass.
Explanation:
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.
Answer:
Almost 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium, sulfur, sodium, chlorine, and magnesium.
Answer:
deep, fertile soils. not too dry and not too wet. warm climate. land suitable for machinery.
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