For Brownian motion of particles of suspensions in liquid. Answer the following:

For Brownian motion of particles of suspensions in liquid. Answer the following: (a) What should be the typical size of suspended particles ?
(b) Bombardments of the suspended …particles by molecules of the liquid are random. We should
then expect equal no. of molecules hitting a suspended particle from all directions. Why is not the net impact zero ?
© Can the assembly of suspended particles by considered a ‘gas’ of ‘heavy molecules’ ? If so, what is the temperature, in tins gas if temperature of the liquid is T?

(a) ${{10}^{-6}}$m
(b) The average number of molecules hit in different directions so their net impact is not zero.
© Yes, since, the heavy gas is in thermal equilibrium with the liquid, its temperature is equal to the temperature of liquid, i.e., T.