The correct order of increasing C-O bond length of CO, CO₂ and CO${}_3^{2-}$ is

• CO${}_3^{2-}$ < CO₂ < CO

• CO₂ < CO${}_3^{2-}$ < CO

• CO < CO${}_3^{2-}$ < CO₂

• CO < CO₂ < CO${}_3^{2-}$

12.

Number of carbon atoms in kerosene is

• C_17-20

• C_12-16

• C_20-25

• C_25-30

A sample of gasoline contain 81% octane and 19% n-heptane. Its octane, number will be

• 19

• 81

• 100

• 62

The IUPAC name of the following compound is:

• 3-methyl cyclohexene

• 1-methyl cyclohex-2-ene

• 6-methyl cyclohexene

• 1-methyl cyclohex-5-ene

Tetrabromoethane on heating with Zn gives

• ethyl bromide

• ethane

• ethyne

• ethene

Which of the following does not exist?

I. HO₃S-S-SO₃H

II. HO-Te-OH

III. HS-S₂-SH

IV. HS-Po-OH

• Only II

• Only III

• II and IV

• I, III and IV

Acidic dichromate ion reacts with hydrogen peroxide to give deep blue colour. This is due to the formation of

• CrO(O)₂

• CrO₅

• Bith (a) and (b)

• None of (a) and (b)

The coordination number and oxidation number X in the following compound [X(SO₄)(NH₃)₅]Cl will be

• 10 and 3

• 2 and 6

• 6 and 3

• 6 and 4

Liquid hydrocarbon is converted into mixture of gaseous hydrocarbons by

• cracking

• oxidation

• hydrolysis

• distillation under reduced pressure

Among the following compound with the lowest pK_a value is