An organic compound contains carbon, hydrogen, and oxygen. Its elemental analysis gave C, 38.71%, and H, 9.67%. The empirical formula of the compound would be:
1. | CH3O | 2. | CH2O |
3. | CHO | 4. | CH4O |
The moles of lead (II) chloride that will be formed from a reaction between 6.5 g of PbO and 3.2 g of HCl are:
1. 0.044
2. 0.333
3. 0.011
4. 0.029
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
1. | 40 mol | 2. | 10 mol |
3. | 20 mol | 4. | 30 mol |
If 2.74 g of the metal oxide contains 1.53 g of metal, then the empirical formula of vanadium oxide is:
(Atomic Mass of V = 52)
1.
2.
3.
4.
25.4 g of and 14.2 g of are made to react completely to yield a mixture of ICI and ICI3. The mole of ICI and ICI3 formed, is respectively -
1. 0.5, 0.2
2. 0.1, 0.1
3. 0.1, 0.3
4. 0.3, 0.4
The vapour density of a mixture containing and is 38.3. The mole of in a 100 g mixture is:
[Vapour density = (Molar mass / 2)]
1. 0.437
2. 0.347
3. 0.557
4. 0.663
The average molar mass of the mixture of and present in the mole ratio of a:b is
20 g mol-1. When the mole ratio is reversed, the molar mass of the mixture will be:
1. | 24 gram | 2. | 42 gram |
3. | 20 gram | 4. | 15 gram |
The haemoglobin from the red blood corpuscles contains approximately 0.33% iron
by mass. The molar mass of haemoglobin is 67,200. The number of iron atoms in each molecule of haemoglobin is :
(atomic mass of iron=56):
1. | 2 |
2. | 3 |
3. | 4 |
4. | 5 |
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