EVERYDAY SCIENCE

Detailed explanation-1: -All compounds are molecules, but not all molecules are compounds. Hydrogen gas (H2) is a molecule, but not a compound because it is made of only one element. Water (H2O) can be called a molecule or a compound because it is made of hydrogen (H) and oxygen (O) atoms.

Detailed explanation-2: -All compounds are molecules, but not all molecules are compounds. That is because a molecule can be made up of two atoms of the same kind, as when two oxygen atoms bind together to make an oxygen molecule. However, all compounds are made up of two or more different types of atoms.

Detailed explanation-3: -Compounds are a group of different atoms and different elements which unite together by the chemical bond. The chemical bond can be of three types, either covalent, ionic or metallic. Similarly, it is important to remember that all compounds are molecules but not all molecules are compounds.

Detailed explanation-4: -A compound is a substance composed of two or more elements, chemically combined in a fixed proportion.

Detailed explanation-5: -Two things are true of all compounds: A compound always has the same elements in the same proportions. For example, carbon dioxide always has two atoms of oxygen for each atom of carbon, and water always has two atoms of hydrogen for each atom of oxygen. A compound always has the same composition throughout.