Q.1.
The ability of anion to bring about coagulation of a given colloid depends upon … [ AIMPT 1997]
-
14%
a) its charge
-
0%
b) the sign of the charge alone
-
29%
c) the magnitude of its charge
-
57%
d) both magnitude and sign of its charge
Q.2.
Alum helps in purifying water by …[ AIEEE 2002]
-
14%
a) Sulphate part which combines with clay particles
-
14%
b) Making mud water soluble
-
0%
c) Forming Si complex with clay particles
-
71%
d) Aluminium which coagulates the mud particles
Q.3.
An increase in the concentration of adsorbate at the surface relative to its concnetration in bulk pahse is called ...
-
83%
a) adsorption
-
0%
b) enthalpy
-
17%
c) absorption
-
0%
d) none of these
Q.4.
At the critical micelle concentration (CMC) the surfactant molecules ..[ AIPMT 1998]
-
17%
a) decompose
-
33%
b) dissociate
-
50%
c) associate
-
0%
d) become completely soluble
Q.5.
Flocculation value is expressed in terms of ...
-
17%
a) mole per milliliter
-
50%
b) millimole per litre
-
0%
c) gram per litre
-
33%
d) mol per ltre
Q.6.
Which one of the following substances gives a positively charged sol?
-
43%
a) Gold
-
0%
b) A metal sulphide
-
43%
c) Ferric hydoxide
-
14%
d) An acidic dye
Q.7.
Finly divided catalyst is most effective because
-
17%
a) less surface area is available
-
33%
b) more energy is strored in catalyst
-
50%
c) provides more active sites
-
0%
d) energy of catalyst become less
Q.8.
According to Freundlich adsorption isotherm, which of the following is correct? [ AIEEE 2012]
-
17%
a) x/m ∝ p
-
33%
b) x/m ∝ p1/n
-
0%
c) x/m ∝ p0
-
50%
d) All the above are correct for
Q.9.
Fog is a colloidal solution of … [ NEET 2016 ]
-
29%
a) Gas in liquid
-
29%
b) Solid in gas
-
0%
c) Gas in gas
-
43%
d) Liquid in gas
Q.10.
On adding few drop of dil. HCl or FeCl3 to freshly precipitated ferric hydroxide, a red coloured colloidal solution is obtained. This phenomenon is known as
-
0%
a) dissolution
-
83%
b) peptization
-
0%
c) protection
-
17%
d) dialysis
Q.11.
For adsorption of a gas on solid, the plot of log x/m Vs log P is linear with slope equal to : (n being a whole number)
-
0%
a) K
-
17%
b) log k
-
17%
c) n
-
67%
d) 1/n
Explanation
Q.12.
Cloud bursts due to ..
-
0%
a) dense clouds are present in the upper atmosphre
-
33%
b) large amout of water present in cloud
-
67%
c) excess of electrostatic induction in the clouds causesw coagulation
-
0%
d) attractioon towards the electrical charges on the earth
Q.13.
The Langmuir adsorption isotherm is deduced by using the assumption that [ AIMPT 2007]
-
0%
a) the adsorption takes place in multilayers
-
67%
b) the adsorption sites are equivalent in their ability to adsorb the particles
-
17%
c) the heat of adsorption varies with coverage
-
17%
d) present in the surface only
Q.14.
Adsorption is accompanied by
-
0%
a) decrease in entropy of the system
-
0%
b) decrease in the enthalpy of the system
-
0%
c) decrease in Gibbs free energy
-
100%
d) All of the these
Q.15.
A catalyst increases the rate of reaction becuase it: [ EAMCET 1992]
-
17%
a) decreases the collision diameter
-
50%
b) increases the activation energy
-
17%
c) decreases the energy barrire for reaction
-
17%
d) increases the activation energy
Q.16.
Tails of coments are visible due to
-
43%
a) Tyndall effect
-
29%
b) Brownian motion
-
29%
c) reflection
-
0%
d) none of these
Q.17.
The coagulating power of electrolytes having ions Na+, Al3+ and Ba2+ for arsenic sulphide solution increases in the order …[ JEE (Mains) 2012]
-
29%
a) Al3+ < Ba2+ < Na+,
-
14%
b) Al3+ < Na+, < Ba2+
-
57%
c) Na+, < Ba2+ < Al3+
-
0%
d) Ba2+ < Na+, < Al3+
Q.18.
When sulphur sol is evaporated solid sulphur is left. On mixing with water no colloidal sol is formed. Sulphur sol is ...
-
57%
a) hydrophobic
-
0%
b) hydrophilic
-
0%
c) reversible
-
43%
d) lyophilic
Q.19.
Which plot is the adsorption isobar for chemisorption?
-
0%
a)
-
17%
b)
-
67%
c)
-
17%
d)
Q.20.
Colloidal solution of arsenious sulphide can be prepared by
-
29%
a) hydrolysis
-
0%
b) electrodispersion
-
0%
c) Condensation
-
71%
d) peptization
Q.21.
The catalyst used in the chamber process of sulphuric acid is ..
-
33%
a) Nitric oxide
-
17%
b) Vanadium pentoxide
-
17%
c) nickel
-
33%
d) Platinum
Q.22.
Assertion: A catalyst lowers the threshold energy level for reaction. Reason: A catalyst combines with reactant to form an exothermic intermediate and provide another pathway to reaction
-
50%
a) Assertion and reason both are correct and Reason is correct explanation of Assertion
-
33%
b) Assertion and reason both are correct and Reason is not correct explanation of Assertion
-
0%
c) Assertion is correct but Reasoning is wrong
-
17%
d) Assertion is wrong but reason is correct
Q.23.
The coagulation values in millimoles per litre of the electrolytes used for the coagulation of As2S3 are given below I. [NaCl] = 52 II. [BaCl2] = 0.69 III. [MgSO4] = 0.22 The correct order of their coagulating power is … [ NEET 2016, Phase II]
-
17%
a) I > II > III
-
50%
b) II > I > I > III
-
33%
c) III > II > I
-
0%
d) III > I > II
Q.24.
Tyndall effect is due to
-
0%
a) reflection of light
-
50%
b) scattering of liight
-
33%
c) absorption of light
-
17%
d) adsorption of light
Q.25.
The suspension of slaked lime in water is known as … [ NEET 2016 phase II]
-
17%
a) lime water
-
0%
b) quicklime
-
83%
c) milk of lime
-
0%
d) Aqueous solution of slaked lime
Q.26.
A sol has positiively charged colloidal particles. Which of the following solutions is required in low concentration for coagulation?
-
17%
a) NaCl
-
50%
b) K4[Fe(CN)6]
-
0%
c) ZnCl2
-
33%
d) Na2SO4
Q.27.
Who coined the term catalysis and awarded Nobel Prize? [ PET (Bihar) 1997]
-
17%
a) Kolbe
-
0%
b) Rutherford
-
33%
c) Wholer
-
50%
d) Berzellius
Q.28.
Which one of the following characteristics is associated with adsorption? [ NEET 2016, phase I]
-
67%
a) ΔG, ΔH and ΔS all are negative
-
17%
b) ΔG, and ΔH are negative but ΔS is positive
-
0%
c) ΔG, and ΔS are negative but ΔH is positive
-
17%
d) ΔG is negative but δH and ΔS are positive