A chemical made up of two or more atoms. The atoms in a molecule can be the same (an oxygen molecule has two oxygen atoms) or different (a water molecule has two hydrogen atoms and one oxygen atom). Biological molecules, such as proteins and DNA, can be made up of many thousands of atoms.
The smallest theoretical quantity of a material that retains the properties exhibited by the material.
A very small mass of matter; a chemical combination of two or more atoms which form a specific chemical substance.
Matter consisting of two or more atoms. The atoms may be the same, as in oxygen (02), or different, as in water (H20).
The smallest independent mass of a substance.
Chemistry, the combination of two or more atoms that form a particular chemical or compound.
The smallest unit of a substance that can exist alone and that has all the chemical properties of that substance. A molecule is a collection of atoms bound tightly together by strong chemical bonds. Many of the Earth’s substances are made of molecules. The nature of each molecule depends on the atoms it contains and how they are bound together.
A combination of two or more atoms that make up a specific chemical compound. The molecule is the smallest quantity into which any substance can be divided and still keep its identifiable characteristics. A molecule of water, for instance, consists of two hydrogen and one oxygen atoms. If any one of the atoms were removed from the molecule, you would no longer have water.
The smallest possible amount of a substance comprising two or more linked atoms which retains the chemical characteristics of that substance. Molecules vary greatly in their size and complexity, ranging from oxygen (two linked oxygen atoms) and water (two hydrogen atoms and one oxygen) to large complex molecules such as deoxyribonucleic acid (DNA) comprising thousands of atoms of carbon, hydrogen, oxygen, nitrogen and phosphorus that form the double-helix structure which helps to create genes, the basic building blocks of the hereditary material of living things.
Any electrically neutral aggregate of atoms held together strongly enough to be considered as a unit. The individual atoms in the molecule may be of the same type or different. Combinations of dissimilar atoms form chemical compounds. The positive and negative electrical charges balance exactly. Excess or deficiency of either positive or negative charge by the loss or acquisition of electrons results in the formation of an ion.
A chemical combination of two or more atoms in definite (fixed) proportions.
The smallest complete unit of a substance that can exist independently and still retain the properties of an element or compound.
The smallest indivisible unit of a substance that possesses the characteristic physical properties of that substance is referred to as a particle. These particles can exist in two forms: they can be simple, like an atom, or compound, unlike an atom.
The tiniest self-sufficient entity of a substance, capable of retaining the distinct properties of that substance. The majority of molecules are composed of two or more atoms joined together. Singularly-atomed molecules are referred to as monatomic molecules.