Question

Does the chemical adsorption increase or decrease when the surface area of adsorbent increases.

Answer 1

Hint : Adsorption is the process in which accumulation of gaseous molecules or species takes place on the surface of solid instead of bulk (absorption). The gaseous species which is accumulated at the surface is called adsorbate while the solid surface on which accumulation takes place is called adsorbent. There are two types of adsorption: Physical adsorption and Chemical adsorption.

Complete Step By Step Answer:
In chemical adsorption, adsorbate is accumulated on the surface of adsorbent by the strong chemical bonds. Thus, chemical adsorption is highly specific and irreversible in nature in contrast to physical adsorption where weak van der waal’s forces of attraction are present between adsorbate and adsorbent. With increase in surface area of adsorbent, more surface is available for the formation of chemical bonds. This thereby increases the chemical adsorption process. On the similar lines, physical adsorption also increases with increase in surface area because more surface is available for the weak van der waal’s forces of attraction.
Hence, both chemical and physical adsorption increase with increase in the surface area of the adsorbent.

Additional Information:
Physical adsorption is non-specific and reversible in nature. Physical adsorption is favorable at low temperature while chemical adsorption is favorable at high temperature.

Note :
It is important to note that the chemical adsorption increases when the surface area of adsorbent increases. With increase in surface area, more surface will be available for the formation of chemical bonds between adsorbate and adsorbent. Moreover, physical adsorption also increases when the surface area of adsorbent increases.