Question

Differenciate between Physical adsorption and Chemical adsorption​

Answer 1

What is Physical adsorption ?

» The process of adsorption takes place by weak vander wall's forces is called physical adsorption.

Eg : NH₃ gas get adsorbed on charcoal surface.

What is chemical adsorption ?

» The process of adsorption takes place by strong chemical forces or chemical bonds (ionic or covalent).

Eg : H₂ gas gets adsorbed on platinum surface.

Difference between Physical adsorption and Chemical adsorption :

Physical adsorption

$\bigstar$ The process of adsorption takes place by weak vander wall's forces.

$\bigstar$ It is favorable at low temperature.

$\bigstar$ It is reversible process.

$\bigstar$ Heat of adsorption is 20 - 40 KJ/mol

$\bigstar$ It is multilayered.

Chemical adsorption

$\bigstar$ The process of adsorption takes place by strong chemical forces.

$\bigstar$ It is favorable at high temperature.

$\bigstar$ It is irreversible process.

$\bigstar$ Heat of adsorption is 80 - 240 KJ/mol

$\bigstar$ It is unilayered.