Question

1. Give the Reason for the following observation:- We get the smell of the perfume sitting several metres away. Condensation of water is not a chemical change.

Answer 1

we get the scent from far away as the gas' molecules are spread and go in all directions

condensation of water is not a chemical change as no new substance is produced

Answer 2

When molecules of some volatile substances from hot sizzling food diffuse into air and reach the odur sensitive part of our nose we have the perception of smell.

At higher temperature of molecules diffuse into air at a faster rate and therefore travel long distances.

Hence the smell of hot sizzling food reaches as quickly even when we are several metres away.

While on the contrary , when the food is called the vapour diffuse is at a slower rate and therefore does not travel longer distances.

So, one has to come closer to have the perception of smell.