Which of The following has a maximum number of molecules?

1. 7g N₂ 

2. 2g H₂ 

3. 16g NO₂ 

4. 16g O₂ 

How much oxygen gas (O₂) at standard temperature (0°C) and pressure (1 atm) is required to completely combust 1 liter of propane gas (C₃H₈) under the same conditions?

1. 7L 
2. 6L
3. 5L
4. 10L

Volume occupied by one molecule of water (density = 1gcm^-3) is 

1. 9.0 x 10^-23 cm³

2. 6.023 x 10^-23 cm³

3. 3.0 x 10^-23 cm³

4. 5.5 x 10^-23 cm³

A metal oxide has the formula Z₂O_3. It can be reduced by hydrogen to give free metal and water. 0.1596g of the metal oxide requires 6 mg of hydrogen for complete reduction. The atomic weight of the metal is

1. 27.9

2. 159.6

3. 79.8

4. 55.8

How many moles of lead (II) chloride will be formed from a reaction between 6.5g of PbO and 3.2g of HCl?

1. 0.044

2. 0.033

3. 0.011

4. 0.029

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

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

Versene, a chelating agent having chemical formula C₂H₄N₂(C₂H₂O₂Na)₄. If each mole of this compound could bind 1 mole of Ca²⁺, then the rating of pure versene expressed as mg of CaCO₃ bound per g of chelating agent is:

1. 100 mg

2. 163 mg

3. 200 mg

4. 263 mg

A gas is found to have the formula (CO)_x. Its VD is 70. The value of x must be:

1. 7 

2. 4

3. 5

4. 6