Which of the following concentration factor is affected by a change in temperature? 

1. Molarity 

2. Molality 

3. Mole fraction 

4. Weight fraction 

An organic compound contains carbon, hydrogen and nitrogen in the mass ratio 9 : 1 : 3.5. If its molar mass is 108 g mol⁻¹, determine its molecular formula.

1. C₆H₈N₂ 

2. C₇H₁₀N 

3. C₅H₆N₃ 

4. C₄H₁₈N₃

The number of atoms in 560 g of Fe (atomic mass 56 g mol^–1) is:

To neutralize 20 mL of 0.1 M aqueous solution of phosphorus acid \((H_3PO_3) \) completely, the volume of 0.1 M aqueous KOH solution required is:

A solution contains \(6.02\times10^{20}\) molecules of urea in 100 mL of solution. Calculate the molarity of the urea solution.
(Given: Avogadro constant, \(N_A=6.02\times10^{23}~mol^{-1}\))

1. 0.002 M

2. 0.01 M

3. 0.02 M

4. 0.1 M

How many moles of magnesium phosphate, Mg₃(PO₄)₂, contain 0.25 moles of oxygen atoms?

What is the molarity of the resulting solution when 480 mL of a 1.5 M non-electrolyte solution is mixed with 520 mL of a 1.2 M solution of the same substance?

1. 2.70 M

2. 1.344 M

3. 1.50 M

4. 1.20 M