Chemistry:2019:CBSE:[All India]: Set-III

Out of Chlorobenzene and Cyclohexyl chloride, Cyclohexyl chloride is more reactive towards nucleophilic substitution reaction due to partial double bond character of C-Cl bond in Chlorobenzene which is difficult to break. Also chlorobenzene is resonance stablised. 

The decreasing order of solubility in water is

C₂H₅NH₂ > (C₂H₅)₂NH > C₆H₅NH₂

Sol is formed when a solid is dispersed in a liquid. Paint is an example of sol.

Schottky defect is shown by ionic compounds having small difference in the size of cations and anions. Out of KCl and AgCl, it is shown by KCl, due to comparable sizes of K⁺ and Cl^– ions.

When zinc oxide is heated, it loses oxygen and there is an excess of Zn²⁺ ions. The number of excess Zn²⁺ ions trapped in the interstitial sites is equal to the number of electrons trapped in neighbouring interstitial sites. The presence of free electrons gives rise to the enhanced electrical conductivity and yellow colour to the crystal.

Amylose is a straight chain polymer of α-D-glucose and is soluble in water.

Amylopectin is a branched chain polymer of α-D-glucose and insoluble in water.

Lactose on hydrolysis with dilute acid gives equimolar mixture of β-D-glucose and β-D-galactose.

The sum of powers of the concentration of the reactants in the rate law expression is called the order of that chemical reaction.

a) First order (The half-life of a first order reaction is independent of initial concentration of the reacting species.)

b) Zero order (For zero order reactions, the half-life depends on the initial concentration of reactant.)

(a) The interactions between chloroform and acetone are stronger than the interactions between either pure chloroform or acetone. Therefore, an increase in temperature is observed on mixing chloroform and acetone.

(b) The solubility of oxygen in water increases with decrease in temperature due to which the aquatic animals are more comfortable in cold water rather than in warm water.