The molality of a 20% (by mass) CaCO₃ solution is : 
(Given: Density of solution is 1.2 gm/ml)

1.	1.25 m	2.	2.5 m
3.	2.08 m	4.	1.5 m

What is the ratio of the number of atoms in 2.2 g of CO₂ and in 1.7 g of NH₃?

An organic substance containing C, H, and O gave the following percentage composition :

C = 40.687%, H = 5.085% and O = 54.228%. The vapour density of this organic substance is 59.

The molecular formula of the compound will be:

1. C₄H₆O₄

2. C₄H₆O₂

3. C₄H₄O₂

4. None of the above

Consider the given reaction, 2SO₂ + O₂ $\to$2SO₃ 

6.4 g SO₂ and 3.2 g O₂ to form SO₃ . The mass of SO₃ formed is:  

1. 32 g
2. 16 g
3. 8 g
4. 4 g

Calculate the total molarity of all the ions present in a solution containing 0.1 M of CuSO₄ and 0.1 M of Al₂(SO₄)₃.

1. 0.2M

2. 0.7M

3. 0.8M

4. 1.2M

When 100 mL of PH₃ is decomposed, it produces phosphorus and hydrogen. The change in volume is:

An element X has the following isotopic composition,

²⁰⁰X : 90%, ¹⁹⁹X : 8.0%, ²⁰²X : 2.0%

The weighted average atomic mass of the naturally occurring element X is closest to: 

In the reaction, 4NH₃(g)+ 5O₂(g) $\to$4NO(g) +6H₂O(l)

When 1 mole of ammonia and 1 mole of O₂  reacts to completion, then:

1 g of magnesium is burnt with 0.56g of oxygen in a closed vessel. The left-out reactant and its quantity are

(At. weight of Mg = 24, O=16)

The mole fraction of the solute in a 1.00 molal aqueous solution is: