Element showing the phenomenon of allotropy is

• aluminium

• tin

• lead

• copper

In which of the following the inert pair effect is most prominent?

• C

• Si

• Ge

• Pb

The alkali metal that reacts with nitrogen directly to form nitride is

• Li

• Na

• K

• Rb

The metal that does not give the borax bead test is

• Chromium

• nickel

• lead

• manganese

A white solid 'A' on heating gives off a gas which turns lime water milky. The residue is yellow when hot but turns white on cooling. This solid 'A' is

• zinc sulphate

• zinc carbonate

• lead sulphate

• lead carbonate

Which of the following compounds exhibits optical isomerism?

• CH₃CH₂COOH

• CH₃CHOHCOOH

• CH₃CH₂CH₂OH

• CH₃CHOHCH₃

The number of possible isomers for compound C₂H₃Cl₂Br is

• 2

• 3

• 4

• 6

Gasoline is obtained from crude petroleum oil by its

• fractional distillation

• vacuum distillation

• steam distillation

• pyrolysis

39.

LPG is a mixture of

• C₆H₁₂ + C₆H₆

• C₄H₁₀ + C₃H₈

• C₂H₄ + C₂H₂

• C₂H₄ + CH₄

Alkene which on ozonolysis yields acetone, is

• CH₂=CH-CH₂-CH₃

• CH₃-CH=CH₂

• CH₃-CH=CH-CH₃

• (CH₃)₂-C=C-(CH₃)₂