General
✓✗The number of chloride ions in 0.1 mol of CaCl2 is
- 6.022 × 1023
- 1.204 × 1023
- 6.022 × 1022
- 3.011 × 1022
General
✓✗The volume of CO2 at STP obtained by the complete decomposition of 9.85 g of BaCO3 is (Ba = 137)
- 0.84 L
- 2.24 L
- 1.12 L
- 0.56 L
General
✓✗A compound has the empirical formula CH2 and molar mass 42 g mol−1. Its molecular formula is
- C2H4
- C4H8
- CH2
- C3H6
General
✓✗A pure sample of water always contains hydrogen and oxygen in the mass ratio 1 : 8, whatever its source. This illustrates the law of
- gaseous volumes
- multiple proportions
- definite proportions
- conservation of mass
General
✓✗The mass of oxygen required for the complete combustion of 2.8 kg of ethylene is
- 96 kg
- 9.6 kg
- 2.8 kg
- 6.4 kg
General
✓✗The number of atoms in 0.1 mol of a triatomic gas is (NA = 6.02 × 1023 mol−1)
- 3.600 × 1023
- 6.026 × 1022
- 1.806 × 1023
- 1.800 × 1022
General
✓✗A mixture of 2.3 g of formic acid and 4.5 g of oxalic acid is treated with conc. H2SO4. The evolved gaseous mixture is passed through KOH pellets. The mass (in g) of the remaining product at STP will be
- 1.4
- 2.8
- 4.4
- 3.0
General
✓✗The number of moles of KMnO4 that react completely with 5 mol of Fe2+ in acid solution (MnO4− + 5Fe2+ + 8H+ → Mn2+ + 5Fe3+ + 4H2O) is
- 1
- 2
- 0.2
- 5
General
✓✗An oxide of iron contains 70% iron by mass. Its formula is (Fe = 56, O = 16)
- Fe2O3
- FeO
- FeO2
- Fe3O4
General
✓✗The amount of glucose required to prepare 250 mL of an M/20 aqueous solution is (molar mass of glucose = 180 g mol−1)
- 2.25 g
- 4.5 g
- 0.44 g
- 1.125 g
General
✓✗Which law is illustrated by the formation of SO2 and SO3 from sulphur and oxygen?
- Law of conservation of mass
- Avogadro's law
- Law of multiple proportions
- Law of definite proportions
General
✓✗In which case is the number of molecules of water maximum?
- 0.00224 L of water vapour at 1 atm and 273 K
- 10−3 mol of water
- 0.18 g of water
- 18 mL of water
General
✓✗The percentage of oxygen in calcium carbonate is (Ca = 40, C = 12, O = 16)
- 60%
- 48%
- 12%
- 40%
General
✓✗In an experiment, 10 mL of a 0.05 M solution of a chloride required 10 mL of a 0.1 M solution of AgNO3. The formula of the chloride is (X stands for the element other than chlorine)
- X2Cl
- XCl4
- XCl2
- X2Cl2
General
✓✗In the Haber process, 30 L of dihydrogen and 30 L of dinitrogen were taken for reaction, which yielded only 50% of the expected product. The composition of the gaseous mixture under the same conditions at the end is
- 20 L ammonia, 10 L nitrogen, 30 L hydrogen
- 20 L ammonia, 20 L nitrogen, 20 L hydrogen
- 10 L ammonia, 25 L nitrogen, 15 L hydrogen
- 20 L ammonia, 25 L nitrogen, 15 L hydrogen