Physical Chemistry
Adsorption of hydrogen gas on glass is endothermic.explain
Adsorption of hydrogen gas on glass is endothermic.explain
1 Answer
Aarti Gupta
Adsorption is a phenomenon of attracting and retaining of an adsorbate substance on the surface of adsorbent resulting of higher concentration of adsorbate molecules on the surface.
Adsorption is generally an exothermic in nature as there is release of energy.
Being spontaneous in nature,the change in free energy(deltaG) is negative.This is due to the fact that entropy change(deltaS) is negative because the adsorbate molecules lose their translational freedom when attatched to the surface of adsorbent.So,in order for deltaG to be negative,deltaH must be sufficiently negative.Such that (deltaG = deltaH – TdeltaS)<0.But in case of some endothermic adsorption reactions like in case of adorption of H2 gas on glass.DeltaH is positve and there is change from----
H2 -----------> 2H,in which deltaS is suffuciently positive such that deltaG remains positive.Thus driving force for such adsorption comes from increased entropy.
Adsorption is generally an exothermic in nature as there is release of energy.
Being spontaneous in nature,the change in free energy(deltaG) is negative.This is due to the fact that entropy change(deltaS) is negative because the adsorbate molecules lose their translational freedom when attatched to the surface of adsorbent.So,in order for deltaG to be negative,deltaH must be sufficiently negative.Such that (deltaG = deltaH – TdeltaS)<0.But in case of some endothermic adsorption reactions like in case of adorption of H2 gas on glass.DeltaH is positve and there is change from----
H2 -----------> 2H,in which deltaS is suffuciently positive such that deltaG remains positive.Thus driving force for such adsorption comes from increased entropy.
Other Related Questions on physical chemistry
Which of the following aqueous solutions remains neutral after
electrolysis
Which of the following aqueous solutions remains neutral after
electrolysis
electrolysis
physical chemistry
Last Activity: 3 Years ago
In the reaction A + 2B ⇌ 2C, if 2 moles of A, 3 moles of B and 2 moles of C are placed in a 2 L flask and
the equilibrium concentration of C is 0.5 mol/L. The equilibrium constant (KC) for the reaction is.....and please tell how you know that the reaction is going forward .. imean how to calculate the reaction quotient ???
In the reaction A + 2B ⇌ 2C, if 2 moles of A, 3 moles of B and 2 moles of C are placed in a 2 L flask and
the equilibrium concentration of C is 0.5 mol/L. The equilibrium constant (KC) for the reaction is.....and please tell how you know that the reaction is going forward .. imean how to calculate the reaction quotient ???
the equilibrium concentration of C is 0.5 mol/L. The equilibrium constant (KC) for the reaction is.....and please tell how you know that the reaction is going forward .. imean how to calculate the reaction quotient ???
physical chemistry
Last Activity: 3 Years ago
True or false when an electron in ground state of hydrogen atom is excited with an energy that is greayer than e2-e1 but less than e3-e1 the electron will get excited n=2
True or false when an electron in ground state of hydrogen atom is excited with an energy that is greayer than e2-e1 but less than e3-e1 the electron will get excited n=2
physical chemistry
Last Activity: 3 Years ago
18 19 gram mixture of na2co3 and nahco3 on heating gives 2.2 gram CO2 gas find the percent nahco3 (by mass) in mixture
18 19 gram mixture of na2co3 and nahco3 on heating gives 2.2 gram CO2 gas find the percent nahco3 (by mass) in mixture
physical chemistry
Last Activity: 4 Years ago