Molecularity of the physical world:

World is composed of a few more than a hundred elements. Elements are building blocks of all the substances that make up all living and non-living things. This means elements are building blocks for everything in the universe. The same elements that make up earth also make up moon.

A careful observation of the physical world reveals that matter you usually occurs as mixtures. Most of the components of these mixtures are elements and compounds that exist as molecules.

Noble gases:

Only noble gases exist as monoatomic molecules. Other substances exist as polyatomic molecules. Air consists of many elements and compounds all existing in molecular form. For instance, O2, N2, CO2, H2O and the noble gases.

Water:

Water a molecular substance cover 70% of the earth's crust it also fills the empty spaces under the earth Rocks and earth are mixtures of numerous compounds.

Giant molecules:

Clay and sand consist of long chains of atoms called giant molecules.

Petroleum and coal that are complex mixtures also contain hundreds of thousands of molecular compounds.

Molecules in living things:

Living things contain thousands of different substances such as carbohydrates, proteins, fats, lipids, DNA, RNA etc. All these substances are molecular in nature.