Aside from carbon and hydrogen, which are always present in organic molecules, what are some other substances they may contain?

Organic compound is defined as a compound that contains carbon . This compound usually occurs in living organisms or any of their byproducts. Their bonds are usually covalent and they form non-polar molecules.

Aside from carbon and hydrogen, organic molecules may contain oxygen and nitrogen.

Atomicity occurs to prevent updates of the database occurring only partially, which can cause greater problems than rejecting the whole series outright.some are monatomic, diatomic, triatomic etc because it shows the number of atoms. for example, monatomic means it contains only one atom.