Question

Smoke is an example of:
A. Solid dispersed in solid
B. Solid dispersed in gas
C. Solid dispersed in liquid
D. Gas dispersed in solid

Answer 1

Hint : As smoke is a solid aerosol. Aerosol is the suspension of fine particles of solid or liquid droplets in air or in the other gas. Smog is similar to smoke and also an example of solid aerosol. Smoke can be described as the collection of unburnt tiny particles dispersed in solid with tiny droplets of tar.

Complete Step By Step Answer:
When there is no complete combustion that is not enough oxygen to burn the fuel completely then there incomplete combustion takes place. In complete combustion, everything is burned, and produces just water and carbon dioxide. But in incomplete combustion, not everything is burned. As smoke is a result of incomplete combustion so it means smoke is a collection of the remaining tiny unburned particles. Each particle is too small and thus we can not see them through our naked eyes, but when they come together, we see them as smoke.
Smoke is a solid aerosol having dispersed phase as solid and dispersion medium as gas.
So, option B is correct.

Additional Information:
If we talk about smoke in wood, When there is wood on a hot fire, the smoke you see is the volatile organic compounds (hydrocarbons) evaporating from the wood. They start to evaporate at about ${149^o}C$ . If the fire is hot enough, the hydrocarbons will burst into flames. Once they burn, there is no smoke because the hydrocarbons are turned into water and carbon dioxide.

Note :
Aerosols can be produced by Aerosol spray, Atomizer nozzle or nebulizer, Electrospray, Electronic cigarette and Vibrating orifice aerosol generator (VOAG). Aerosols can be used in various purposes like to test aerosols for calibrating instruments, performing research, and testing sampling equipment and air filters. It is also to deliver deodorants, paints and other consumer products in sprays. It is widely used for medical treatment of respiratory disease and also in fuel injection systems and other combustion technology.