The number of atoms in 0.1 mole of a triatomic gas is:
(NA=6.02 x1023mol-1)
| 1. | 6.026 x 1022 | 2. | 1.806x1023 |
| 3. | 3.600 x 1023 | 4. | 1.800 x 1022 |
Which of the following combinations illustrates the law of reciprocal proportions?
1. \(\mathrm{N}_2 \mathrm{O}_3, \mathrm{~N}_2 \mathrm{O}_4, \mathrm{~N}_2 \mathrm{O}_5 \)
2. \(\mathrm{NaCl}, \mathrm{NaBr}, \mathrm{Nal}\)
3. \(\mathrm{CS}_2, \mathrm{CO}_2, \mathrm{SO}_2 \)
4. \(\mathrm{PH}_3, \mathrm{P}_2 \mathrm{O}_3, \mathrm{P}_2 \mathrm{O}_5\)
The formula of an acid is The mass of 0.0242 moles of the acid is 1.657 g.
The atomic weight of X is:
| 1. | 35.5 | 2. | 28.1 |
| 3. | 128 | 4. | 19.0 |
Calculate the mole fraction of the solute in a 1.00 m aqueous solution.
| 1. | 0.177 | 2. | 0.771 |
| 3. | 0.0534 | 4. | 0.0177 |
Concentrated aqueous sulphuric acid is 98% H2SO4 by mass and has a density of 1.80 g mL-1.
The volume of acid required to make one litre of 0.1 M H2SO4 solution is:
| 1. | 11.10 mL | 2. | 16.65 mL |
| 3. | 22.20 mL | 4. | 5.55 mL |
A gaseous mixture of and gas contains 66 mass % of . The vapour density of the mixture is:
1. 6.1
2. 5.4
3. 2.7
4. 10.8
The percentage of oxygen present in the compound is-
1. 23.3%
2. 45.36%
3. 41.94%
4. 17.08%
| 1. | 2 |
| 2. | 3 |
| 3. | 4 |
| 4. | 5 |
Which mixture is lighter than humid air?
1.
2.
3.
4.
At 100 ºC and 1 atm, if the density of liquid water is 1.0 g cm–3 and that of water vapor is 0.0006 g cm-3, then the volume occupied by water molecules in 1 litre of steam at that temperature will be:
| 1. | 6 cm3 | 2. | 60 cm3 |
| 3. | 0.6 cm3 | 4. | 0.06 cm3 |
The maximum number of molecules is present in which of the following?
1. 15 L of gas at STP
2. 5 L of gas at STP
3. 0.5 g of gas
4. 10 g of gas
The number of moles present in 2.5 litres of 0.2 M are:
1. 0.25
2. 0.5
3. 0.75
4. 0.2
The weight of one molecule of a compound C60H122 is
1.
2.
3.
4.
Determine the mass percentage of urea in a solution prepared by mixing equal moles of urea and water.
1. 22.086
2. 11.536
3. 46.146
4. 76.92
The number of valence electrons present in 0.53 grams of Na2CO3 is:
1.
2.
3.
4.
The molality of 0.01 M Na2CO3 solution is:
(The density of the solution is 1.1 g/ml)
1.
2.
3.
4.
lf NA is Avogadro's number, then the number of valence electrons in 4.2 g of nitride ions (N) will be:
| 1. | 3.2 NA | 2. | 1.6 NA |
| 3. | 2.4 NA | 4. | 1.2 NA |
What is the molarity of solution that has a density of 1.84 g/cc at 35°C and contains 98% by weight?
1. 1.84 M
2. 81.4 M
3. 18.4 M
4. 184 M
Calculate the number of moles of oxygen (O) atoms in 126 amu of HNO3.
1. 2
2.
3. 6
4.