Which mode of expressing concentration is independent of temperature?

1. Molality

2. Percent by mass

3. Mole fraction

4. All of the above 

12 g of Mg (atomic mass = 24) will react completely with an acid to yield:

1. One mole of H₂ 

2. A half mole of H₂

3. One mole of O₂

4. None of the above

A metal M forms a compound M₂HPO₄. The formula of the metal sulphate is:

1. M₂SO₄ 

2. MSO₄

3. M(SO₄${)}_2$

4. M₂(SO₄)₃

The product of atomic mass and specific heat of metal is approximately 6.4. This was given by:

1. Dalton's law

2. Avogadro's law

3. Newton's law

4. Dulong Petit's law

One litre N₂, 7/8 litre O₂ and 1 litre CO are taken in a mixture under indentical conditions of P and T. The amount of gases present in mixture is given by:

1. ${\mathrm{\omega }}_{{\mathrm{N}}_2}={\mathrm{\omega }}_{{\mathrm{O}}_2}>{\mathrm{\omega }}_{\mathrm{CO}}$ 

2. ${\mathrm{\omega }}_{{\mathrm{N}}_2}={\mathrm{\omega }}_{\mathrm{CO}}>{\mathrm{\omega }}_{{\mathrm{O}}_2}$ 

3. ${\mathrm{\omega }}_{{\mathrm{N}}_2}={\mathrm{\omega }}_{{\mathrm{O}}_2}={\mathrm{\omega }}_{\mathrm{CO}}$

4. ${\mathrm{\omega }}_{\mathrm{CO}}>{\mathrm{\omega }}_{{\mathrm{N}}_2}>{\mathrm{\omega }}_{{\mathrm{O}}_2}$

The molality of a 15% (w/vol.) solution of H₂SO₄ of density 1.1g/cm³ is:

1. 1.2 mol/kg

2. 1.4 mol/kg

3. 1.8 mol/kg

4. 1.6 mol/kg

Equal volumes of 0.1 M AgNO₃ and 0.2 M NaCl are mixed. The concentration of N${\mathrm{O}}_3^{-}$ ions in the mixture will be:

A solution contains Na₂CO₃ and NaHCO₃. 10 mL of the solution required 2.5 mL of 0.1 M H₂SO₄ for neutralisation using phenolphthalein as indicator. Methyl orange is then added when a further 2.5 mL of 0.2 M H₂SO₄ was required. The amount of Na₂CO₃ and NaHCO₃ in 1 litre of the solution is:

1. 5.3g and 4.2g

2. 3.3g and 6.2g

3. 4.2g and 5.3g

4. 6.2g and 3.3g

A partially dried clay mineral contains 8% water. The original sample contained 12% water and 45% silica. The percentage of silica  in the partially dried sample is nearly: