101. Gold number of a lyophilic sol is such a property that :
A
The larger its value, the greater is the peptizing power.
B
The lower its value, the greater is the peptizing power.
C
The lower its value, the greater is the protecting power.
D
The larger its value, the greater is the protecting power.
Answer :
The lower its value, the greater is the protecting power.
102.
For the adsorption of solution on a solid surface, $$\frac{x}{m} = k{C^{\frac{1}{n}}},$$ Adsorption isotherm of $$\log \left( {\frac{x}{m}} \right)$$ and $$\log C$$ was found of the type. This is when
A
$$C = 0$$
B
$$\frac{1}{n} = 0$$
C
$$C = {\text{constant}}$$
D
$$C = 2\,M$$
Answer :
$$\frac{1}{n} = 0$$
103. If $$x$$ is amount of adsorbate and $$m$$ is amount of adsorbent, which of the following relations is not related to adsorption process?
A
$$\frac{x}{m} = f\left( T \right)\,{\text{at constant}}\,p$$
B
$$p = f\left( T \right){\text{at constant}}\left( {\frac{x}{m}} \right)$$
C
$$\frac{x}{m} = p \times T$$
D
$$\frac{x}{m} = f\left( p \right){\text{at constant}}\,T$$
Answer :
$$\frac{x}{m} = p \times T$$
104. Which of the following examples is correctly matched ?
A
Butter - gel
B
Smoke - emulsion
C
Paint - foam
D
Milk - aerosol
Answer :
Butter - gel
105. The activity of an enzyme becomes ineffective
A
at low temperature
B
at atmospheric pressure
C
at high temperature
D
in aqueous medium
Answer :
at high temperature
106. Which of the following is not correct regarding the adsorption of a gas on the surface of solid?
A
On increasing pressure, adsorption keeps on increasing.
B
Enthalpy and entropy changes are negative.
C
Chemisorption is more specific than physisorption.
D
It is a reversible reaction.
Answer :
On increasing pressure, adsorption keeps on increasing.
107.
Colloidal solutions of metals like gold can be prepared when their salt solutions react with certain substances like $$SnC{l_2},$$ ,formaldehyde, phenyl hydrazine, etc.
$$2AuC{l_3} + 3SnC{l_2} \to 3SnC{l_4} + \mathop {2Au}\limits_{{\text{Sol}}} $$
The above method is an example of
A
reduction method
B
oxidation method
C
hydrolysis method
D
double decomposition method
Answer :
reduction method
108.
When a colloidal solution is viewed from the direction at right angles of light beam, the path of the beam is illuminated due to scattering of light. In the figure $$(A)$$ and $$(B)$$ are
A
$$A$$ - Tyndall cone, $$B$$ - Scattered light
B
$$A$$ - Scattered light, $$B$$ - Tyndall cone
C
$$A$$ - Tyndall cone, $$B$$ - Blind spot
D
$$A$$ - Tyndall effect, $$B$$ - Tyndall cone
Answer :
$$A$$ - Tyndall cone, $$B$$ - Scattered light
109. When $$KCl{O_3}$$ is heated, it decomposes into $$KCl + {O_2}.$$ If some $$Mn{O_2}$$ is added, the reaction goes much faster because
A
$$Mn{O_2}$$ decomposes to give $${O_2}$$
B
$$Mn{O_2}$$ provides heat by reacting
C
better contact is provided by $$Mn{O_2}$$
D
$$Mn{O_2}$$ acts as a catalyst
Answer :
$$Mn{O_2}$$ acts as a catalyst
110. Shape-selective catalysis is a reaction catalysed by
A
zeolites
B
enzymes
C
platinum
D
Ziegler-Natta catalyst
Answer :
zeolites