224 ml of a triatomic gas weighs 1g at 273 K and 1 atm. The mass of one atom of this gas is:
1. 8.30 × 10–23 g
2. 2.08 × 10–23 g
3. 5.53 × 10–23 g
4. 6.24 × 10–23 g
Number of H-atom in 1.7 g of NH3 is:
(NA = Avogadro number)
1. NA
2. 0.1×NA
3. 0.3 × NA
4. 3 × NA
The relative molecular mass of calcium carbonate is 100. What is the minimum volume of 2.0 M hydrochloric acid that would be needed to completely react with 2.0 g of calcium carbonate?
1. 40 cm3 | 2. 20 cm3 |
3. 30 cm3 | 4. 5 cm3 |
The maximum number of atoms is present in which of the following -
1. | 1 g of Mg(s) | 2. | 1 g of O2 (g) |
3. | 1 g of Li(s) | 4. | 1 g of Ag(s) |
The density of a 2 M aqueous solution of NaOH is 1.28 g/. The molality of the solution is:
[molecular mass of NaOH = 40 ]
1. | 1.20 m | 2. | 1.56 m |
3. | 1.67 m | 4. | 1.32 m |
When 7.3 g of magnesium bicarbonate (Mg(HCO3)2) is decomposed by heating, how much carbon dioxide gas (in mL) is released at STP?
1. 1000 mL
2. 1120 mL
3. 2230 mL
4. 3240 mL
1. | 40 mol | 2. | 10 mol |
3. | 20 mol | 4. | 30 mol |
1.0 g of magnesium is burnt with 0.56 g O2 in a closed vessel. Which reactant is left in excess and by how much? (At. wt. Mg = 24; O = 16)
1. | Mg, 0.16 g | 2. | , 0.16 g |
3. | Mg, 0.44 g | 4. | , 0.28 g |