Hydrocarbon

Question 1

LNG is termed as…..

Answer 1

Liquified Natural Gas

Question 2

Petrol diesel and kerosene are obtained by……… of petroleum

Answer 2

Fractional distillation

Question 3

Coal gas is obtained by…………of coal gas.

Answer 3

destructive distillation

Question 4

Statement 1: Natural gas is found in upper strata during drilling of oil wells.
Statement 2: Higher hydrocarbons are used as solvents for paints and also as starting materials for manufacture of many dyes and drugs.

Answer 4

Both are correct

Question 5

Assertion:Alkane were earlier known as paraffins (latin : parum, little; affinis, affinity)
Reason: These hydrocarbons are inert under normal conditions as they do not react with acids, bases and other reagents.

Answer 5

Both are correct and correct explanation

Question 6

In alkane bond length of C—C is greater than C—H

Answer 6

True

Question 7

Alkane physical states

Answer 7

C 1 to 4 member gas
C 5 to17 member liq
C 18 and + solids

Question 8

Petrol and lower fractions of petroleum are also used for dry cleaning of clothes to remove grease stains.

With increase in number of branched chains, the molecule attains the shape of a sphere. This results in smaller area of contact and therefore weak intermolecular forces between spherical molecules, which are overcome at relatively lower temperatures.

Answer 8

Both statements are correct

Question 9

Incomplete combustion of alkanes with insufficient amount of air or dioxygen, carbon black is formed which is used in the manufacture of ink, printer ink, black pigments and as filters.

Answer 9

True

Question 10

dodecane, a constituent of kerosene oil on heating to 973K in the presence of platinum, palladium or nickel gives a mixture of

Answer 10

heptane and pentene.

Question 11

Assertion: rotation around a C-C single bond is not completely free.
Reason: It is hindered by a small energy barrier of 1-20 kJ mol–1 due to weak repulsive interaction between the adjacent bonds.

Answer 11

Both are correct and correct explanation

Question 12

Assertion: Rotation about carbon-carbon single bond in ethane is almost free for all practical purposes.
Reason: Even at ordinary temperatures, the ethane molecule gains thermal or kinetic energy sufficient enough to overcome this energy barrier of 12.5 kJ mol–1 through intermolecular collisions.

Answer 12

Both are correct and correct explanation

Question 13

Allene physical state:

Answer 13

First 3 are gases
4 to 14 liquids
Higher solids

Question 14

Statement 1: Ethene is colourless gas with faint sweet smell
Statement 2; alkene show a regular increase in boiling point with increase in size i.e., every – CH2 group added increases boiling point by 20–30 K.

Answer 14

Both are correct

Question 15

First stable member of alkyne family is……..

Answer 15

Ethyne aka acetylene

Question 16

Alkyne physical state

Answer 16

First 3 gas
Next 8 liquids
Higher solids

Question 17

Statement 1: Ethyene has a characteristic odour
Statement 2: Alkynes are lighter than water

Answer 17

Both are True

Question 18

Benzene was isolated by……….. in 1825

Answer 18

Michale faraday