Amolecule is made up of
a. two or more atoms covalently bonded together.
b. two or more elements next to each other.
c. two different atoms ionically bonded together.
d. two different elements next to each other.

A molecule is made of "two or more atoms covalently bonded together" or option A. A molecule are made of of atoms that have a chemical bond together. Molecules are a group of atoms bonded together to represent a compound. A example of molecules would be like oxygen.

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it can be icreased by increasing pressure.

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