Calculate the mass percentages of sodium (Na), sulfur (S), and oxygen (O), respectively, in sodium sulphate (Na₂SO₄):

1. 32.4%, 45.05% and 22.6%

2. 22.6%, 45.05% and 32.4%

3. 32.4%, 22.6% and 45.05%

4. 45.05%, 32.4% and 22.6%

The mass of sodium acetate (CH₃COONa) required to make 500 mL of 0.375 molar aqueous solution would be -

Molar mass(sodium acetate) = 82.0245 g/mol

1. 17.86g

2. 31.76g

3. 20.34g

4. 15.38g

The concentration of 69% nitric acid (by mass) in a sample with a density of 1.41 g / mL will be :

1. 15.44 mol/L

2. 17.14 mol/L

3. 20.06 mol/L

4. 12.26 mol/L

The amount of copper (in grams) that can be obtained from 100 g of copper sulphate (CuSO₄) is:

1. Fe₃O₂

2. Fe₂O₂

3. Fe₂O₃

4. Fe₃O₄

The average atomic mass of chlorine using the following data would be:

1. 38.4527 u

2. 37.4527 u

3. 36.4527 u

4. 35.4527 u

Determine the number of moles of hydrogen atoms present in 3 moles of ethane (C₂H₆):

1. 18.069 × 10²³

2. 1.8 × 10²³

3. 18

4. 6 × 10²³

Find the concentration of sugar, C₁₂H₂₂O₁₁, in mol L⁻¹ when 20 g of sugar is dissolved in enough water to make 2 L of solution.

1. 0.29 mol/L

2. 0.029 mol/L

3. 0.35 mol/L

4. 0.032 mol/L

How much volume of methanol is needed to prepare 2.5 L of a 0.25 M solution, if the density of methanol is 0.793 kg/L?

1. 22.25 mL
2. 24.78 mL
3. 25.22 mL 
4. 28.52 mL

If the mass of air per unit area at sea level is 1034 g cm^–2, pressure in pascal will be:

1. 1.01332 × 10⁵ Pa

2. 1.01332 × 10⁶ Pa

3. 1.01332 × 10⁷ Pa

4. 1.01332 × 10⁸ Pa