A compound has the empirical formula CH2O. Its vapour density is

Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsMultiple Choice Questions

141.

If an organic compound has C = 40%, H = 13.3% and N = 46.67%, then the empirical formula of this compound is

  • CH4N

  • C2H8N2

  • CH3N

  • None of these


142.

Which of the following units of energy, represents maximum amount of energy?

  • Calorie

  • Joule

  • Erg

  • Electron volt


Advertisement

143.

A compound has the empirical formula CH2O. Its vapour density is 30. Its molecular formula is

  • C2H4O2

  • C2H6O

  • C2H6O2

  • C2H4O


A.

C2H4O2

2 × vapour density = molecular weight

                 2 × 30 = 60

 Molecular weight of compound = 60

(Empirical formula) × n = molecular formula

 (12 + 1 × 2 + 16) × n = 60

 n = 2

So, (CH2O) × 2 = moleuclar formula

Therefore, molecular formula is C2H4O2.


Advertisement
144.

Combustion of liquid benzene in oxygen occurs as 2C6H6 + 15O2 → 12CO2 + 6H2O. At STP, what volume (in litre) of oxygen is required for the full combustion of 3.9 g liquid benzene?

  • 11.2 L

  • 22.4 L

  • 8.4 L

  • 7.4 L


Advertisement
145.

64 g of an organic compound contains 24 g of carbon, 8 g of hydrogen and the rest oxygen. The empirical formula of the compound is

  • CH2O

  • C2H4O

  • CH4O

  • C2H8O


146.

1f 20 mL of 0.4 N NaOH solution completely neutralises 40 mL of a dibasic acid, the molarity of the acid solution is

  • 0.1 M

  • 0.2 M

  • 0.3 M

  • 0.4 M


147.

Molality of a solution is equal to

  • number of moles of solutenumber of litres of solution

  • number of g-equivalents of solutenumber of litres of solution

  • number of moles of solutenumber of kilogram of solvent

  • number of moles of a componenttotal number of moles of all components


148.

The sample with largest number of atoms is

  • 1g O2(g)

  • 1g Ni(s)

  • 1g B(s)

  • 1g N2(g)


Advertisement
149.

An organic compound containing C, H and N gives the following on analysis : C = 40%, H = 13.33% and N = 46.67%. What would be its empirical formula?

  • C2H7N

  • C2H7N2

  • CH4N

  • CH3N


150.

The normality of 0.2M H3PO2 is

  • 0.2 N

  • 0.4 N

  • 0.6 N

  • 0.06 N


Advertisement