Q.1
Hydrolysis of Sucrose is catalysed by
  • a) H+
  • b) enzymes
  • c) Mineral acids
  • d) all of these
Q.2
Which statements are correct for chemical adsorption?
  • a) Reactant molecules are adsorbed on surface by can der Waal's force
  • b) It is irreversible with temperature suslly occurring at high temerature
  • c) Strong multilayer, directional and non-specific
  • d) It requires no activation energy
Q.3
The stability of the dispersed phase in a lyophobic collid is due to
  • a) high viscosity of the medium
  • b) the formation of electrical layer between two phases
  • c) high surface tension of soolution
  • d) None of the sawer is correct
Q.4
The curve showing the variation of adsorption with pressure at constant temperaure is called..
  • a) an isoster
  • b) adsorption isotherm
  • c) adsorption isobar
  • d) all of these
Q.5
Which one of the following forms micelles in aqueous solution above certain concentration? AIMPT 2005]
  • a) Urea
  • b) Dodecyl trimethyl ammonium chloride
  • c) Pyridinium chloride
  • d) Glucose
Q.6
Butter is a colloid form in which
  • a) fat is dispered in water
  • b) globules of casen dispersed in fat
  • c) suspension of fat in water
  • d) water is disperesed in fat
Q.7
Assertion: Enzymes are proteins and enzyme catalyzed reaction are called biological catalysis Reason: The activity of enzyme as catalyst is increased in presence of vitamins
  • a) Assertion and reason both are correct and Reason is correct explanation of Assertion
  • b) Assertion and reason both are correct and Reason is not correct explanation of Assertion
  • c) Assertion is correct but Reasoning is wrong
  • d) Assertion is wrong but reason is correct
Q.8
Lyophobic colloids are ...
  • a) reversible colloids
  • b) irreversible colloids
  • c) gum, proteins
  • d) protective colloids
Q.9
The ability of ion to bring about coagulation of a given colloidal solution depends upon
  • a) the size of its ion
  • b) the magnitude of charge
  • c) the sign of charge
  • d) both magnitude and sign of charge
Q.10
Hydrolysis of protein in stomach and in intestine takes place due to action of enzyme
  • a) pepsine in stomach only
  • b) trypsin in intestine only
  • c) pepsin in stomach and trypsin in intestine
  • d) HCl in stomach
Q.11
Which is universally correct for catalyst?
  • a) A catalyat chemically changes at the end of reaction
  • b) All kind of catalysts undergoes catalytic poisoning
  • c) A catalyst remains unchanged chemically at the end of chemical reaction
  • d) Catalyst accelerates the reaction
Q.12
Assertion: Presence of catalyst alter the individual energy of reactants and products Reason: The numerical value of Δ H or Δ U for the given reaction does not change in presence of catalyst
  • a) Assertion and reason both are correct and Reason is correct explanation of Assertion
  • b) Assertion and reason both are correct and Reason is not correct explanation of Assertion
  • c) Assertion is correct but Reasoning is wrong
  • d) Assertion is wrong but reason is correct
Q.13
When dilute aqueous solution of AgNO3 (excess) added to KI solution, positively charged sol particles of AgI are formed due to adsorption of ion
  • a) K+
  • b) Ag+
  • c) I-
  • d) NO3-
Q.14
Assertion: Term catalyst means specifically for a substance that accelerates the reaction Reason: The terms inhibitor is commonly used for substances which retards the rate of reaction
  • a) Assertion and reason both are correct and Reason is correct explanation of Assertion
  • b) Assertion and reason both are correct and Reason is not correct explanation of Assertion
  • c) Assertion is correct but Reasoning is wrong
  • d) Assertion is wrong but reason is correct
Q.15
A dilute solution of litmus becomes colourless on shaking with charcoal. This is due to ..
  • a) absorption
  • b) adsorption
  • c) chemical reaction
  • d) both (a) and (b)
Q.16
etergent action of synthetic detergents is due to their ...
  • a) ionisation
  • b) emulsifying properties
  • c) interfacial area
  • d) high molar mass
Q.17
An arsenious sulphide solution carries a negative charge. The maximum precipitating power of this sol is possessed by ..
  • a) K2SO4
  • b) CaCl2
  • c) Na3PO4
  • d) AlCl3
Q.18
Which is correct in case of van der Waals' adsorption?
  • a) Low temerature, low pressure
  • b) High temerature and high pressure
  • c) Low temerature, high pressure
  • d) High temerature and low pressure
Q.19
Size of colloidal particles is
  • a) < suspension particles
  • b) > true solution particles
  • c) < true solution particles
  • d) = suspension particles
Q.20
Which of the following forms cationic micelles above certain concentration? [AIPMT 2004]
  • a) Sodium ethyl sulphate
  • b) Sodium acetate
  • c) Urea
  • d) Cetyl trimethyl ammonium bromide
Q.21
Inhibitor is one ..
  • a) takes reaction in backward direction
  • b) takes reaction in forward direction
  • c) promotes by products
  • d) decreases the rate of reaction
Q.22
Pick out wrong statement
  • a) Cleansing action is not related to micelles
  • b) Micelles are formed by surfactant molecules above the Critical Micelle Concentration (CMC)
  • c) The conductivity of a solution having surfactant molecules decreases sharply at the CMC
  • d) Lower is the CMC of detergent, more is its detergency
Q.23
In Langmuir’s model of adsorption of gas on solid surface [ AIEEE 2006]
  • a) The mass of gas striking a given area of surface is independent of the pressure of the gas
  • b) The adsorption at a single site on the surface may involved multiple molecules at the same time.
  • c) The rate of dissociation of adsorbed molecules from the surface does not depend on the surface covered
  • d) The mass of gas striking a given area of surface is proportional to the pressure of the gas
Q.24
Protons accelerate the hydrolsis of esters. This is an example of
  • a) hetrogeneous catalysis
  • b) homogeneous catalysis
  • c) acid base catalysis
  • d) Both b and c
Q.25
Silver iodide is used for producing artificiial rains because silver iodide
  • a) is easy to spray at high altitde
  • b) is nsoluble in water
  • c) has crystal structure similar to ice
  • d) is easy to synthesize
Q.26
which is not a property of hydrophilic sols
  • a) High concnetrations of dispersed phase can be easily attained
  • b) Coagulation is reversible
  • c) The affinity between disperse phase and dispersion medium is weak.
  • d) The viscosity of colloid is higher than that of the dispersion medium
Q.27
In colloidal state, particle size ranges from
  • a) 1 to 10 Å
  • b) 20 to 50 Å
  • c) 10 to 1000 Å
  • d) 1 to 280 Å
Q.28
Enzyme catalysts are ...
  • a) highly specific in nature
  • b) non-specific
  • c) solids
  • d) always liquid
Q.29
Which of the following is not a characteristic of chemisorption?
  • a) Adsorption is irreversible
  • b) ΔH is of the order of 900 kJ
  • c) Adsorption is specific
  • d) Adsorption increases with increase of surface area
Q.30
In Freundlich adsorption isotherm, the value of 1/n is [ AIMPT 2012]
  • a) between 0 and 1 in all cases
  • b) between 2 and 4 in all cases
  • c) 1 in case of physical adsorption
  • d) 1 in case of chemisorption
0 h : 0 m : 1 s