A solution of two components containing ${\mathrm{n}}_1$ moles of the 1^st component ${\mathrm{n}}_2$ moles of the 2^nd component is prepared. ${\mathrm{M}}_1<mspace\; width="1em"></mspace>\mathrm{and}<mspace\; width="1em"></mspace>{\mathrm{M}}_2$ are the molecular weights of component 1 and 2 respectively. If d is the density of the solution in g ${\mathrm{mL}}^{-1}$, ${\mathrm{C}}_2$ is the molarity and ${\mathrm{x}}_2$ is the mole fraction of the 2^nd component, then ${\mathrm{C}}_2$ can be expressed as: 

1. ${\mathrm{C}}_2=\frac{{\mathrm{dx}}_2}{{\mathrm{M}}_2+{\mathrm{x}}_2\left({\mathrm{M}}_2-{\mathrm{M}}_1\right)}$

2. ${\mathrm{C}}_2=\frac{1000<mspace\; width="1em"></mspace>{\mathrm{dx}}_2}{{\mathrm{M}}_1+{\mathrm{x}}_2\left({\mathrm{M}}_2-{\mathrm{M}}_1\right)}$

3. ${\mathrm{C}}_2=\frac{1000{\mathrm{x}}_2}{{\mathrm{M}}_1+{\mathrm{x}}_2\left({\mathrm{M}}_2-{\mathrm{M}}_1\right)}$

4. ${\mathrm{C}}_2=\frac{{\mathrm{dx}}_1}{{\mathrm{M}}_2+{\mathrm{x}}_2\left({\mathrm{M}}_2-{\mathrm{M}}_1\right)}$

What is the molality of a solution containing 20% (mass/mass) KI in water?
(molar mass of KI = 166 g mol^–1)

1. 1.51
2. 7.35
3. 4.08
4. 2.48

The molarity of a solution obtained by mixing 750 mL of 0.5M HCl with 250 ml of 2M HCl will be:

1. 1.75 M

2. 0.975 M

3. 0.875 M

4. 1.00 

Two solutions of a substance (non electrolyte) are mixed in the following manner.
480 mL of 1.5 M first solution +520 mL of 1.2 M second solution.
What is the molarity of the final mixture?

1. 2.70 M

2. 1.344 M

3. 1.50 M

4. 1.20 M

\(6.02\times10^{20}\) molecules of urea are present in 100 mL of its solution. The concentration of urea solution is:
(Avogadro constant, \(N_A=6.02\times10^{23}~mol^{-1}\))

1. 0.001 M

2. 0.01 M

3. 0.02 M

4. 0.1 M

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:

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

1. Molarity 

2. Molality 

3. Mole fraction 

4. Weight fraction