Question

Give reason for the following observation.
a) We can smell the jasmine flower while we are sitting several metres away.
b) The level of water remains the same when a pinch of salt is dissolved in it.

TNSCERT Class 7 General Science Ch5 Matter in our Surroundings

Answer 1

a) dis is becoz of diffusion as particles move from d area of higher concentration to lower concentration 
b) dis happens becoz d particles of salt take place bet d gaps of particles of water

Answer 2

Smell of Jasmine flower:

a) We can smell the jasmine flower while we are sitting several meters away due to diffusion. The flower contains solvent which carries pleasant smelling vapor. They diffuse quite fast and can reach a person sitting several meters away.  

Same water level even after dropping pinch of salt:

b) The level of water remains the same when a pinch of salt is dissolved in it. It is because the molecules of the salt get embedded in the space which is available in the water molecules.