| 1. | 40 mol | 2. | 10 mol |
| 3. | 20 mol | 4. | 30 mol |
An organic compound contains carbon, hydrogen, and oxygen. If elemental analysis reveals 38.71% carbon and 9.67% hydrogen, which of the following is its empirical formula?
| 1. | CH3O | 2. | CH2O |
| 3. | CHO | 4. | CH4O |
The volume of oxygen gas (O2) needed to completely burn 1 L of propane gas (C3H8) (both O2 & propane measured at 0°C and 1 atm) will be:
1. 7 L
2. 6 L
3. 5 L
4. 10 L
25.3 g of sodium carbonate, Na2CO3, is dissolved in enough water to make 250 mL of a solution. If sodium carbonate completely dissociates, the molar concentrations of sodium ion, Na+ and carbonate ion, are respectively:
(molar mass of Na2CO3 = 106g mol-1)
1. 0.955 M and 1.910 M
2. 1.910 M and 0.955 M
3. 1.90 M and 1.910 M
4. 0.477 M and 0.477 M
100 mL of solution having molarity of 1M and density 1.5 g/mL is mixed with 400 mL of water. The molarity of the solution will be: (final density is 1.25 g/mL )
| 1. | 4.4 M | 2. | 0.145 M |
| 3. | 0.52 M | 4. | 0.227 M |
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 |
An aqueous solution of NaOH has a molarity of 2 M and a density of 1.28 g cm⁻³.
Calculate the molality of the solution:
[Given: Molecular mass of NaOH = 40 g mol-1]
| 1. | 1.20 m | 2. | 1.56 m |
| 3. | 1.67 m | 4. | 1.32 m |
An organic substance containing C, H, and O gave the following percentage composition :
C = 40.687%, H = 5.085% and O = 54.228%. The vapour density of this organic substance is 59.
The molecular formula of the compound will be:
1. C4H6O4
2. C4H6O2
3. C4H4O2
4. None of the above
ln a closed vessel, 50 ml of completely reacts with 200 ml of C2 according to the following equation:
What will be the composition of the gaseous mixture in the system?
1. 100 ml
2. 25 ml
3. 75 ml
4. 10 ml
What is the ratio of the number of atoms in 2.2 g of CO2 and in 1.7 g of NH3?
| 1. | 1/2 | 2. | 1/8 |
| 3. | 3/8 | 4. | 3/2 |