Molecule a has a molecular weight of 175 and molecule b has a molecular weight of 450. a 0.1 m solution of each is placed on agar gel. which molecule will diffuse more rapidly through the agar?

Molecule A

The process in which movement of molecules or atoms occurs from high concentration region to low concentration region until the concentration gradient attains a state of equilibrium is said to be diffusion.

The rate of diffusion is directly related with temperature, pressure and concentration gradient i.e. difference between the two concentrations. Thus, the rate of diffusion will be faster with the higher pressure, temperature and concentration gradient.

The rate of diffusion is inversely related with molecular weight and resistance. Thus, higher the molecular weight and resistance, slower will be the rate of diffusion.

Molecule A has molecular weight = 175 and

Molecule B has molecular weight = 450

The molecular weight of molecule A is smaller than the molecular weight of molecule B. Thus, molecule A will diffuse more faster than molecule B as rate of diffusion is inversely proportional to molecular weight.