<span>lipids. Lipids are sometimes referred to as fats. Lipids are a naturally occurring substance. Their main function in humans are storing energy and as part of cell membranes. Lipids are also used in the cosmetics industry. Glucose is a simple sugar found in humans and plants.</span>
The most abundant of all of the isotopes of an element will be the one who's mass the mass of element is closest to. In this case, the mass of atomic carbon is closest to the mass of carbon-12.
Thus, Carbon-12 is the most abundant isotope.
Because they have the same number of electrons in the outer shell, they have the same reactivity (they all want to lose/gain a certain amount of electrons to have a full shell of 8), so they have the similar melting, boiling points etc because they all undergo very similar reactions to certain factors so have similar outcomes
