Question 9 :
The reactions in which catalyst and reactant have one phase are known as :

Question 12 :
The simplest way, to check whether a system is a colloid, is by

Question 14 :
The addition of alcohol to a saturated aqueous solution of calcium acetate first forms a sol and then sets to a gelatinous mass called solid alcohol which is a :

Question 18 :
The separation of colloidal particles (or purification of sol) from particles of molecular dimensions is known as :

Question 21 :
Dispersed phase consists of discrete particles significantly larger than ordinary molecules and in this small particles of solute is diffused in solvent. 

Question 22 :
In presence of a catalyst, the activation energy is lowered by 3 kcal at $27^o C$. Hence, the rate of reaction will increase by:

Question 26 :
Which one of the following statements is incorrect in the case of heterogeneous catalysis

Question 29 :
Platinised asbestos helps in the formation of $SO_{3}$, from $SO_{2}$ and $O_{2}$. But, if even a small amount of $As_{2}O_{3}$ acts here as

Question 31 :
Assertion: Positive catalyst decrease the energy of activation. Reason: Negative catalyst increase the energy of activation.

Question 32 :
Assertion: A catalyst is more effectively in finely divided form. Reason: Finely divided form has more surface area.

Question 34 :
Dispersion medium in which dispersed phase is present. This consists of continuously interlinked molecules.

Question 35 :
The substance which decreases the rate of a chemical reaction is called:

Question 36 :
Assertion: Hydrolysis of ester is an example of auto-catalytic reaction. Reason: A catalyst speeds up the process without participating in the mechanism.

Question 37 :
Assertion: Threshold level of energy is lowered in presence of catalyst. Reason: The catalyst forms an intermediate adsorbed complex and adsorption is exothermic.

Question 38 :
Assertion: In chemisorption, adsorption first increases with temperature and then decreases. Reason: Heat keeps on providing more and more activation energy.

Question 42 :
Finally divided catalyst has a greater surface area and has greater catalytic activity than the compact solid. If a total surface area of $6291456\, cm^2$ is required for adsorption of gaseous reaction in a catalyzed reaction,then how many splits should be made in a cube of exactly 1 cm in length.[Given: One split of a cube gives eight cubes of the same size]

Question 44 :
Which of the following kinds of catalysis can be explained by the adsorption theory?

Question 48 :
Whenever a mixture of gases is allowed to come in contact with a particular adsorbent under the same conditions, the more strong adsorbate is adsorbed to greater extent irrespective of its amount present. For e.g. $\displaystyle H_{2}O$ is adsorbed to a greater extent on silica gel than $\displaystyle N_{2}$ and $\displaystyle O_{2}$. This shows that some adsorbates are preferentially adsorbed. It is also observed that preferentially adsorbable adsorbents can displace a weakly adsorbed substance from the surface of an adsorbent. Which of the following gase(s) is/are adsorbed to maximum extent?