Q.1.
Ultramicroscope works on the principle of ...
-
20%
a) light reflection
-
10%
b) light absorption
-
60%
c) light scattering
-
10%
d) light polarization
Q.2.
Rate of physisorption increases with … [ IIT 2003]
-
50%
a) Decrease in temperature
-
0%
b) Decrease in surface area
-
50%
c) Increase in temperature
-
0%
d) Decrease in pressure
Q.3.
The enzyme ptyalin used for digestion of food is present in ...
-
50%
a) saliva
-
0%
b) blood
-
50%
c) intestine
-
0%
d) adrenal glands
Q.4.
Which caharacteristic is not correct for physical adsprption? [ AIEEE 2003]
-
12%
a) Adsorption on solid is reversible
-
12%
b) Adsorption is spontaneous
-
50%
c) Adsorption increases with increase in temperature
-
25%
d) Both enthalpy and entropy change of adsorption are negative
Q.5.
Which of the following decomposes of urea in ammonia and carbon dioxide
-
0%
a) pepsin
-
17%
b) Cellulase
-
67%
c) urease
-
17%
d) trypsin
Q.6.
Lyophiliic sols are more stable than lyophobic sols because
-
0%
a) the colloidal particles have positive charge
-
0%
b) the colloidal particles negative charge
-
29%
c) the colloidal particles are solvated
-
71%
d) there are strong electrostatic repulsions between the negatively charged colloidal particles
Q.7.
Which process does not involve a catalyst? [ KCET 1991]
-
67%
a) Thermite process
-
17%
b) Ostwald's process
-
17%
c) Contact process
-
0%
d) Haber's process
Q.8.
The temerature above which micelle formation occurs is ...
-
17%
a) Inverson temerature
-
50%
b) Kraft's temerature
-
17%
c) Charles' temerature
-
17%
d) Caffeine
Q.9.
Protons accelerate the hydrolysis of esters. this is an example of
-
12%
a) a promoter
-
38%
b) a hetrogeneous catalyst
-
38%
c) an autocatalyst
-
12%
d) acid-base catalyst
Q.10.
Which acts as poison to platinum ( a catalyst) in the manufacture of H2SO4 by contact process?
-
60%
a) Arsenious oxide
-
20%
b) CO2
-
0%
c) CO
-
20%
d) Sodium sulphide
Q.11.
The dispersed phase in colloidal ion(III) hydroxide and colloidal gold is positively and negatively charged respectively, which of the following statement is not correct …[ AIEEE 2005\
-
20%
a) Coagulation in both sol can be brought about by electrophoresis
-
0%
b) Na2SO4 solution causes coagulation in both sol
-
60%
c) Mixing of two sols have no effect
-
20%
d) MgCl2 solution coagulates gold sol readily than iron (IIII) hydroxide sol
Q.12.
According to Langmuir theory of adsorption
-
40%
a) amount of gas adsorbed goes on increasing with pressure
-
0%
b) the adsorbate molecules are held on the surface by chemical forces
-
60%
c) amount of gas adsorbed decreases and then increases with decrease of temperature
-
0%
d) amount of gas adsorbed goes on increasing with pressure
Q.13.
Colloidal solution commonly used in treatment of skin diseases is
-
0%
a) colloidal sulphur
-
17%
b) colloidal solver
-
50%
c) colloidal magnesium
-
33%
d) colloidal gold
Q.14.
Flocculation value is expressed in terms of
-
40%
a) millimole/ Litre
-
0%
b) mole/ Litre
-
20%
c) gram/ Litre
-
40%
d) mole/millilitre
Q.15.
Which of the following is not colloid?
-
33%
a) Chlorophyll
-
0%
b) Smoke
-
33%
c) Ruby glass
-
33%
d) Milk
Q.16.
In the titration between oxalic acid and acidified potassium permanganate, the manganous salt formed during the reaction catalyses the reaction. The manganous salt acts as.
-
0%
a) postive catalyst
-
40%
b) a promoter
-
60%
c) an autocatalyst
-
0%
d) noone of thse
Q.17.
Which statement is wrong?
-
0%
a) Reaction with higher activation energy has higher rate constant
-
60%
b) The catalyst does not alter the equilibrium of a reaction
-
10%
c) Half-life period of a first order reaction is independent of initial cooncentratiion
-
30%
d) In the endothermic reaction, the activation energy of the reaction is higher than that of heat of reaction
Q.18.
For the coagulation of 100mL of As2S3 sol, 5 ml of 1M NaCl is required. The flocculation value of NaCl is
-
0%
a) 50
-
0%
b) 5
-
80%
c) 47.6
-
20%
d) None of these
Explanation
Q.19.
Methylene blue, from its aqueous solution, is adsorbed on activated charcoal at 25°C. For this process, the correct statement is …[ JEE 2013]
-
0%
a) The adsorption is irreversible
-
60%
b) The adsorption is accompanied by a decrease in enthalpy
-
20%
c) The adsorption requires activation at 25&dgeC
-
20%
d) The adsorption increases with increase of temperature
Q.20.
The spontaneous outcome of internal liquid from gels is called
-
20%
a) swelling
-
0%
b) thixotropy
-
0%
c) synerisis
-
80%
d) all of these
Q.21.
A catalyst
-
0%
a) increases temperature
-
40%
b) changes the energy of activation
-
20%
c) affects the stste of equilibrium
-
40%
d) affects the forward and backward reactions of a reversible reaction differently
Q.22.
Which is used in the Haber's processs for the manufacture of NH3 [ Rootkee 1993]
-
80%
a) Fe + Mo
-
0%
b) Al2O3
-
20%
c) CuO
-
0%
d) Pt
Q.23.
Function of catalyst for a reversible reaction is to
-
20%
a) supplies energy to the reaction
-
20%
b) decreases the time to reach equiliibrium
-
20%
c) increases the equilibrium concentration of the products
-
40%
d) change the equilibrium constant of the reaction
Q.24.
dentify the correct statement regarding enzymes …[ AIEEE 2004]
-
20%
a) Enzymes are normally heterogeneous catalyst that are very specific in their action
-
0%
b) Enzymes are specific biological catalysts that can not be poisoned
-
80%
c) Enzymes are specific biological catalysts that can normally function at very high temperature ( T ≈ 1000K)
-
0%
d) Enzymes are specific biological catalyst that posses well defined active state
Q.25.
in homogeneous catalytic reactions, the rate of reaction
-
20%
a) depends on free energy
-
20%
b) depends on physical state of the catalyst
-
40%
c) depends on concentration of ctalyst
-
20%
d) independent of concentration of ctalyst
Q.26.
Which of the following is most effective in causing the coagulation of ferric hydroxide sol?
-
0%
a) KCl
-
17%
b) KNO3
-
17%
c) K2SO4
-
67%
d) K3[Fe(CN)6]
Q.27.
The critical micellization concentration (CMC) is
-
40%
a) the concentration at which miiscellization begins
-
0%
b) the concentration at which true solution beginss
-
40%
c) the concentration at which one molar electrolyte is present per 1000g of solution
-
20%
d) the concentration at which solute anda solution form equilibrium
Q.28.
According to the ‘adsorption theory of catalysis, the speed of the reaction increases because ..[ AIMPT 2003]
-
20%
a) adsorption produces hat which increases the speed of the reaction
-
0%
b) adsorption lowers the activation energy of the reaction
-
80%
c) the concentration of reactant molecules at the active centres of the catalyst becomes high due to adsorption
-
0%
d) in the process of adsorption, the activation energy of the molecules becomes large
Q.29.
If the dispered phase in a liquid and the dispersion medium is a solid, the colloid is known as
-
0%
a) a foam
-
50%
b) a sol
-
17%
c) an emulsion
-
33%
d) a gel
Q.30.
Which are correct in the case of enzyme catalysis?
-
40%
a) Enzyme work best at high temperature
-
0%
b) Enzyme work in acidic or basic medium
-
60%
c) Enzymes are highly specific for substrates
-
0%
d) Enzyme catalysis involves iincrease of activation energy