Condensation occurs through the release of energy
It can be a compound or a single element. An element is a pure substance that cannot be separated into simpler substances by chemical or physical means. There are about 117 elements, butcarbon, hydrogen, nitrogen and oxygen are only a few that make up the largest portion of Earth.
I would say d.
To calculate the average mass of the element, we take the summation of the product of the isotope and the percent abundance. We calculate as follows:
Average atomic mass = .374 ( 184.953 amu ) + .626 ( <span>186.958 amu ) = 186.208 amu
Hope this answers the question. Have a nice day.</span>