The addition of a catalyst during a chemical reaction alters which of the following quantities?
(a) Internal energy
(b) Enthalpy
(c) Activation energy
(d) Entropy
Which one of the following characteristics is associated with adsorption?
(1) G, H and S all are negative
(2) G and H are negative but S is positive
(3) G and S are negative but H is positive
(4) G is negative but H and S are positive
Which one of the following statements is incorrect about enzyme catalysis?
(a) Enzymes are mostly proteinous in nature
(b) Enzyme action is specific
(c) Enzymes are denaturated by ultraviolet rays and at high temperature
(d) Enzymes are least reactive at optimum temperature
The protecting power of lyophilic colloidal sol is expressed in terms of
(a) coagulation value
(b) gold number
(c) critical micelle concentration
(d) oxidation number
The stabilization of the dispersed phase in a lyophobic sol is due to
(1) The viscosity of the medium
(2) The surface tension of the medium
(3) Liking for the medium
(4) The formation of an electrical layer between the two phases
The process of converting precipitate into collidal solution on adding an electrolyte is called:
(A) Peptisation
(B) Dialysis
(C) Electro-osmosis
(D) Eelectrophoresis
Emulsifying agent stabilized the emulsion of oil in water by
1. Forming an interfacial film between suspended particles and the medium
2. Dissolving the suspended particles into the medium completely
3. Coagulating the suspended particles from medium completely
4. Converting the suspended particles into vapor completely
If of charcoal having, active surface area 1000 is used for monolayer absorption of a gas having molecular radius cm, then volume of the absorbed gas at STP is [Avogadro's number = ]
1. 11.2 L
2. 22.4 L
3. 7.46 L
4. 3.73 L
Among the following, the surfactant that will form micelles in aqueous solution at the highest molar concentration
1.
2.
3.
4.
Some types of gels like gelatin liquify on shaking, thereby changing into sols. The sols on standing change back into a gel. The process is known as
1. Syneresis
2. Thixotropy
3. Peptisation
4. Imbition