Question

Fog, mist and rain: when a large mass of air containing dust particles is cooled below its dew point, the moisture from the air condenses on the surface of these particles forming fine droplets. These droplets being colloidal in nature continue to float in air in the form of mist or for. Clouds are aerosols having small droplets of condensation in them.

Answer 1

Hint : Everything that surrounds us is called an environment; this environment may be natural like ponds or man-made like cities. The branch of science which is responsible for the study and the development of the understanding of the chemical phenomena is called Environmental Sciences.

Complete Step By Step Answer:
Everything in our surrounding is termed as environment. The environment around is generally considered to be pure, but if any contamination to this pure environment takes place it is regarded as pollution. The substances that may be living or non-living responsible for the pollution are termed as pollutants.
Pollution may be of land, air or water, each and every type of pollution is harmful for some or another organism.
Particulates are small sized particles not visible to naked human eye but act as pollutants. Mists are the liquids mixed in air and are floating in air. Dusts are the solid particles mixed in air and are floating in air. Smog is the mixture of fog and smoke. The smog is dangerous as it is inflammable due to the presence of various inflammable chemicals.

Note :
To overcome the problem of pollution, a new type of sustainable chemistry has been developed by Paul Anastas called Green Chemistry. The main aim of this branch of chemistry is to reduce or totally eliminate the use and the production of toxic products. It also aims for sustainable development which means development in such a way that our up-coming generation has not to pay for our bad deeds.