A. electron. The nucleus has protons and neutrons, quark is the particle which forms protons and neutrons.
Half life is the time taken by a radioactive isotope to decay by half its original mass. In this case, the halflife of the radioactive isotope is 5000 years.
Initially the mass is 100 %; thus the mass that will be left will be given by;
New mass = Original mass × (1/2)^n where n is the number of half lives;
n = 10000/5000 = 2
New mass = 100% ×(1/2)^2
= 100 % × 1/4
= 25%
Therefore; the mass left after 10000 years is 25% or 1/4 of the original mass.
If the diatomic molecule consists of atoms from two different elements, then it is aheteronuclear diatomic molecule. There are seven elements that naturally occur as homonucleardiatomic molecules in their gaseous states: hydrogen,nitrogen, oxygen, fluorine,chlorine, bromine, and iodine
Explanation:
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