The density of a 2 M aqueous solution of NaOH is 1.28 g/$c{m}^3$. The molality of the solution is: 
[molecular mass of NaOH = 40 $gmo{l}^{-1}$]

1.	1.20 m	2.	1.56 m
3.	1.67 m	4.	1.32 m

To produce 20 moles of ammonia via Haber's process, how many moles of hydrogen molecules are required?

Concentrated aqueous sulphuric acid is 98% H₂SO₄ by mass and has a density of 1.80 g mL^-1. The volume of acid required to make one litre of 0.1 M H₂SO₄ solution is:

1. 11.10 mL

2. 16.65 mL

3. 22.20 mL

4. 5.55 mL

The moles of lead (II) chloride that will be formed from a reaction
between 6.5 g of PbO and 3.2 g of HCl are:

1. 0.044
2. 0.333
3. 0.011
4. 0.029

The volume of oxygen gas (O₂) needed to completely burn 1 L of propane gas (C₃H₈)  (both O₂ & propane measured at 0°C and 1 atm) will be:
1. 7 L
2. 6 L
3. 5 L
4. 10 L

The volume occupied by one water molecule (density = 1 g cm^-3) is:

1. $9.0\times {10}^{-23}$ $$ ${\mathrm{cm}}^3$

2. $6.023\times {10}^{-23}$ $$ ${\mathrm{cm}}^3$

3. $3.0\times {10}^{-23}$ $$ ${\mathrm{cm}}^3$

4. $5.5\times {10}^{-23}$ $$ ${\mathrm{cm}}^3$

10 g of hydrogen and 64 of oxygen were filled in a steel vessel and exploded. The amount of water produced in this reaction will be:

1. 2 mol

2. 3 mol

3. 4 mol

4. 1 mol

The number of atoms in 0.1 mole of a triatomic gas is (N_A= 6.02 x 10²³ mol^-1):

1. $6.026\times {10}^{22}$

2. $1.806\times {10}^{23}$

3. $3.600\times {10}^{23}$

4. $1.800\times {10}^{22}$

25.3 g of sodium carbonate, Na₂CO₃, is dissolved in enough water to make 250 mL of a solution. If sodium carbonate completely dissociates, the molar concentrations of sodium ion, Na⁺ and carbonate ion, $C{O}_3^{2-}$are respectively:
(molar mass of Na₂CO₃ = 106g mol^-1)

1. 0.955 M and 1.910 M
2. 1.910 M and 0.955 M
3. 1.90 M and 1.910 M
4. 0.477 M and 0.477 M

Mole fraction of solute in a 1.00 molal aqueous solution is:
1.  0.0177
2.  0.0344
3.  1.770
4.  0.1770