The maximum number of atoms is present in which of the following -

1. 1 g of Mg_(s)  

2. 1 g of O_{2 (g)}

3. 1 g of Li_(s)    

4. 1 g of Ag_(s)   

The same number of molecules as 16 g of dioxygen is present in:

1. 16 g O${}_3$

2. 16 g SO${}_2$

3. 32 g SO${}_2$

4. All of the above

The number of  moles  present in 2.5 litres of 0.2 M  ${\mathrm{H}}_2{\mathrm{SO}}_4$ are:

1. 0.25

2. 0.5

3. 0.75

4. 0.2

Which of the following statements is correct?

1. 1 mole of electrons weights 5.4 mg .
2. 1 mole of electrons weights 5.4 kg. 
3. 1 mole of electrons weights 0.54 mg. 
4. 1 mole of electrons has 1.6$\times {10}^{-19}$ C of charge.

Which of the following is the odd one with regard to mass?

1. 1 g atom of sulphur 

2. 0.5 moles of CO${}_2$ 

3. 1 mole of O${}_2$ 

4. 3 × 10 ²³ molecules of SO${}_2$

The weight of one molecule of a compound C₆₀H₁₂₂ is

1. $5.005\times {10}^{23 }\mathrm{g}$

2. $6.023\times {10}^{23} \mathrm{g}$

3. $4.1\times {10}^{-21} \mathrm{g}$

4. $1.4\times {10}^{-21}\mathrm{g}$

Breakfast cereal is advertised to contain 110 mg of sodium per 100 grams of cereal. The percent of sodium in the cereal is:

1. 0.110%

2. 0.0110 %

3. 11.0%

4. 0.22 %

The percentage weight of Zn in white vitriol [ZnSO₄.7H₂O] is approximately equal to (Zn=65, S=32, O=16 and H=1)

1. 21.56%

2. 32.58%

3. 22.65%

4. 26.55%

A gaseous mixture contains O₂ and N₂ in the ratio 1:4 by weight. Then the ratio of their number of molecules in the mixture is

1. 3:32

2. 7:32

3. 1:4

4. 3:16

1cc N₂O at STP contains: