A:-Bicarbonates of Na and K

B:-Bicarbonates of Ca and Mg

C:-Chlorides and sulphates of Ca and Mg

D:-Chlorides and sulphates of Na and K

Correct Answer:- Option-C
Question39:-Role of a catalyst in a chemical reaction is

A:-To decrease activation energy

B:-To increase activation energy

C:-To increase heat of reaction

D:-To decrease heat of reaction

Correct Answer:- Option-A
Question40:-Characteristics of transition element

A:-Show variable oxidation state

B:-Forms alloys

C:-Form coloured compounds

D:-All the above

Correct Answer:- Option-D
Question41:-In [*"Ni(CO)_4"" ], the oxidation number of Nickel is

3+ نم

B:-+2

C44

D:-Zero

Correct Answer:- Option-D
Question42:-Primary, secondary and tertiary amines can be distinguished by Hinsberg reagent, which is

A:-Benzoyl chloride

B:-Benzene sulphonyl chloride

C:-Acetic anhydride

D:-Benzyl chloride

Correct Answer:- Option-B
Question43:-The monomer of PVC is

A:-Ethene

B:-Vinyl chloride

C:-Styrene

D:-Tetra Fluoro ethane

Correct Answer:- Option-B
Question44:-Tyndall effect is

A:-Scattering of light by colloidal particle

B:-Refraction of light by colloidal particle

C:-Absorption of light by colloidal particle

D:-Reflection of light by colloidal particle

Correct Answer:- Option-A
Question45:-Which of the following battery is used in automobiles?

A:-Nickel-cadmium cell

8:-` "1 2-0 2" fuel cell

C:-Lead storage battery

D:-Mercury cell

Correct Answer:- Option-C
Question46:-Emulsion is an example of colloidal system of

A:-Liquid dispersed in gas

B:-Solid dispersed in gas

C:-Liquid dispersed in liquid

D:-Liquid dispersed in solid

Correct Answer:- Option-C
Question47:-The volume of 1 mol of gas at STP is

A:-22.4 ml

B:-22.4 L

C:-2.24 ml

D:-2.24L

Correct Answer:- Option-B