The mass of carbon anode consumed (giving only carbon dioxide) in the production of 270 kg of aluminium metal from bauxite by the Hall process is (at. mass of Al = 27)

1. 180 kg

2. 270 kg

3. 540 kg

4. 90 kg

In the Haber process, 30 L of dihydrogen and 30L of dinitrogen were taken for the reaction, which yielded only 50% of the expected product. What will be the composition of the gaseous mixture under the said conditions in the end?

1. 20L ammonia, 10L nitrogen, 30L hydrogen

2. 20L ammonia, 25L nitrogen, 15L hydrogen

3. 20L ammonia, 20L nitrogen, 20L hydrogen

4. 10L ammonia, 25L nitrogen, 15L hydrogen

The number of atoms in 4.25 g of NH₃ is approximately

1. 4 x 10²³ 

2. 2 x 10²³ 

3. 1 x 10²³ 

4. 6 x 10²³ 

In the reaction, 4NH₃(g)+ 5O₂(g) $\to$4NO(g) +6H₂O(l)

When 1 mole of ammonia and 1 mole of O₂  reacts to completion, then

1. 1.0 mole of H₂O is produced 

2. 1.0 mole of NO will be produced

3. All the oxygen will be consumed

4. All the ammonia will be consumed

An element X has the following isotopic composition:

²⁰⁰X : 90%, ¹⁹⁹X : 8.0%, ²⁰²X : 2.0%

The weighted average atomic mass of the naturally occurring element X is closest to 

1. 201 u

2. 202 u

3. 199 u

4. 200 u

0.24g of a volatile gas, upon vaporisation, gives 45 mL vapour at NTP. What will be the vapour density of the substance?

(Density of H₂ = 0.089)

1. 95.93

2. 59.93

3. 95.39

4. 5.993

The hydrated salt, Na₂SO₄.nH₂O, undergoes a 55% loss in mass on heating and becomes anhydrous. The value of n will be:

1. 5

2. 3

3. 7

4. 10

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

1. One mole of H₂ 

2. Half mole of H₂

3. One mole of O₂

4. None of the above

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

1. 1.2

2. 1.4

3. 1.8

4. 1.6

Which mode of expressing concentration is independent of temperature?

1. Molality

2. Percent by mass

3. Mole fraction

4. All of the above