It s very important to identify your area of interest and level of commitment to the nursing field and then formulate a plan that will help you meet the nursing requirements to get you to the career level you desire.
Oxygen would be (O2). The 2 is a subscript. Sub means below. The 2 is written to the right of and below the O. A pair of oxygen atoms is a molecule of oxygen. A molecule is the smallest particle of a substance that exists independently. Molecules of most elements are made up of only one of atom of that element. Oxygen, along with nitrogen, hydrogen, and chlorine are made up of two atoms. Look at the model of oxygen above.
A molecule is what you get when any atoms join together. A compound is what you get when atoms of two or more different elements join together. All compounds are molecules, but not all molecules are compounds. Water is a molecule because it is made from atoms that have been chemically combined. It is also a compound because the atoms that make water are not all the same-some are oxygen and some are hydrogen. Oxygen in the atmosphere is a molecule because it is made from two atoms of oxygen. It is not a compound because it is made from atoms of only one element-oxygen. This type of molecule is called a diatomic molecule, a molecule made from two atoms of the same type.