DIRECTIONS : These are Assertion-Reason type question.Question contains two statements:Statement-1 (Assertion) and Statement-2 (Reason). Answer these questions from the following four options.
Statement-1 :According to Freundlich:\(\frac{x}{m} = kp^{\frac{1}{n}}\)
Statement-2 :The isotherm shows variation of the amount of gas adsorbed by the adsorbent with temperature.
Solution
Statement - 1 is true but Statement - 2 is false.Freundlich adsorption isotherm gives an empirical relationship between the quantity of gas adsorbed by unit mass of solid adsorbent and pressure at a particular temperature.
DIRECTIONS : These are Assertion-Reason type question.Question contains two statements:Statement-1 (Assertion) and Statement-2 (Reason). Answer these questions from the following four options.
Statement-1 :The enthalpy of physisorption is greater than chemisorption. Statement-2 :Molecules of adsorbate and adsorbentare held by van der Waal’s forces in physisorption and by chemical bonds in chemisorption
Solution
Statement - 1 is false but Statement - 2 is true. The enthalpy of chemisorption is of the order of 40 - 400 kJ mol–1 while for physical adsorption it is of the order of 20 -40 kJ mol–1.
The coagulating power of electrolytes having ions Na+, Al3+ and Ba2+ for arsenic sulphide sol increases in the order :
Solution
According to Hardy Schulze rule, greater the charge on cation, greater is its coagulating power for negatively charged sol(As2S3), hence the correct order of coagulating power : Na+ < Ba2+ < Al3+
Among the electrolytes Na2SO4, CaCl2, Al2(SO4)3 and NH4Cl, the most effective coagulating agent for Sb2S3 sol is
Solution
As Sb2S3 is a negative sol, so Al2(SO4)3 will be the most effective coagulant due to higher positive charge on Al (Al3+) – Hardy-Schulze rule
Which of the following statements is incorrect regarding physisorptions?
Solution
Adsorption is an exothermic process, hence ∆H will always be negative.
The protecting power of lyophilic colloidal sol is expressed in terms of :
Solution
The lyophobic sols are less stable than lyophilic sols.The lyophilic sols are thus used to protect the lyophobic sols. This property of lyophilicsols is known as protective action of lyophilic sols which is represented by gold number
Which one of the following, statements is incorrect about enzyme catalysis?
Solution
Enzymes are most reactive at optimum temperature. The optimum temperature for enzyme activity lies between 40°C to 60°C.
In Freundlich Adsorption isotherm, the value of 1/n is :
Solution
If xis amount of adsorbate and m is amount of adsorbent,which of the following relations is not related to adsorption process ?
The Langmuir adsorption isotherm is deduced by using the assumption
Solution
Langmuir adsorption isotherm is based on the assumption that every adsorption site is equivalent and the ability of a particle to bind there is independent of whether nearby sites are occupied or not.
