1. How many molecules are there in one mole of H2O?

a. 6.023*10¹⁹
b. 6.023*10²³
c. 1.084*10¹⁸
d. none

2. A flask contains 500cm3 of SO2 at STP. The flask contains

a. 40g
b. 100g
c. 50g
d. 1.427g

3. A necklace has 6g of diamond in it . What are the number of atoms in it

a. 6.023*10²³
b. 12.04 *10²³
c. 1.003*10²³
d. 3.01*10²³

4. What is mass of aluminium in 204g of aluminium oxide Al2O3

a. 26g
b. 27g
c. 54g
d. 108g

5. The reactant that is consumed earlier and gives least quantity of product is called

a. reactant in excess
b. limiting reactant
c. stichiometry
d. stichiometric amount

6. Which of following compounds contains the highest percentage by mass of nitrogen

a. NH3
b. N2H4
c. NO
d. NH4OH

7. Vitamin-A has a molecular formula C₂₀H₃₀O . The number of vitamin-A molecules in 500mg of its capsule will be

a. 6.023*10²³
b. 1.05*10²¹
c. 3.01*10²²
d. 3.01*10²¹

8. When one mole of each of following is completely burnt in oxygen, which will give the largest mass of CO2?

a. carbon monoxide
b. diamond
c. ethane
d. methane

9. One mole of ethanol and one mole of ethane have an equal

a. mass
b. number of atoms
c. number of electron
d. number of molecules

10. Methane reacts with steam to form H2 and CO as shown below CH4 + H2O ……> CO + 3H2 . What amount of H2 can be obtained from 100cm3 of methane and STP?

a. 300cm³
b. 200cm³
c. 150cm³
d. 100cm³

11. How many moles of oxygen are needed for the complete combustion of two moles of butane

a. 2
b.8
c. 10
d. 13

12. If four moles of SO2 are oxidized to SO3. how many moles of oxygen molecules are required.

a. 0.5
b. 1.0
c. 1.5
d. 2.0