How many moles are there in 3.0 g of \(O_2\)? [O = 16.0]
- A. 0.0093 moles.
- B. 0.0930 moles.
- C. 0.0625 moles.
- D. 0.6250 moles.
Species that occur in a reaction pathway but not in the overall reaction are known as
- A. Reactants
- B. Inhibitors
- C. Products
- D. Intermediates
A mixture containing two salts of different solubility can be separated by
- A. chromatography.
- B. crystallization.
- C. distillation.
- D. evaporation.
Which of the following statements is correct?
- A. Addition reactions occur between alkanes and chlorine.
- B. Butane has a lower boiling point than propane.
- C. Pentane has five isomers.
- D. An alkane with 49 carbon atoms contains 100 hydrogen atoms
Dilute trioxonitrate (V) acid does not produce hydrogen when it reacts with metals because
- A. it reacts with the product.
- B. it is highly corrosive.
- C. there is no visible reaction.
- D. it is a strong oxidizing agent.
Which of the following properties does not give evidence of the kinetic theory of matter?
- A. Diffusion
- B. Melting
- C. Polymerization
- D. Evaporation
Which of the elements in the table below would react more readily with chlorine?
|
Element |
Ionization energy (KJ \(mol^{-1} \times 10^{-3}\)) |
| W | 12.0 |
| X | 21.0 |
| Y | 106.0 |
| Z | 200.0 |
- A. Y and Z only
- B. X and Z only
- C. W and X only
- D. W and Z only
The formation of a bond between hydrogen and a highly electronegative atom results in
- A. polarity
- B. electrovalent bond.
- C. dipole
- D. metallic bond
Alkenes can be manufactured by
- A. the combustion of alkanes.
- B. the cracking of hydrocarbons.
- C. polymerization reactions.
- D. addition of hydrogen to unsaturated vegetable oils.
The following steps are scientific methods except
- A. experimentation
- B. problem identification
- C. Analysis
- D. Open-mindedness
Which of the following reactions represents the hydrolysis of an alkanoate?
- A. \(CH_3COOH + OH^- ⇌H^+⇌ CH_3COO^- + H_2O\)
- B. \(CH_3COOH + C_2H_5OH ⇌H^+⇌ CH_3COOC_2H_5 + H_2O\)
- C. \(CH_3COOC_2H_5 + H_2O ⇌H^+⇌ CH_3COO^- + CH_3CH_2OH\)
- D. \(CH_3COOCH_2CH_3 + H_2O ⇌H^+⇌ CH_3COOH + CH_3CH_2OH\)
The following statements are correct except
- A. energy is released when liquids change to solids.
- B. carbon atoms in gaseous methane are further apart than those in solid diamond.
- C. there is large decrease in the volume of a solid metal when pressure is applied to it.
- D. particles move faster in the gaseous state than in the liquid state.
The vapour density of an organic compound with the molecular formula \(C_2H_4O_2\), is
[H=1.0, C=12.0, O= 16.0]
- A. 40
- B. 120
- C. 65
- D. 30
Which of the following sketches is a graphical representation of Boyle’s law?
- A. A
- B. B
- C. C
- D. D
Which of the following scientists formulated the law of conservation of mass?
- A. A. Lavoisier
- B. J. Dalton
- C. R. Boyle
- D. J. Proust
The first definition of an element was made by
- A. J. Dalton.
- B. A. Lavoisier.
- C. R. Boyle.
- D. J. J. Thompson.
Charcoal is used in the decolourization of sugar because of its
- A. absorption property.
- B. amorphous property.
- C. oxidizing property.
- D. adsorption property.
If the molar mass of X(HCO3)\(_{2}\) is 162 g mol\(^{-1}\), determine the relative atomic mass of X.
[H = 1.0, C = 12.0, 0 = 16.0]
- A. 40
- B. 48
- C. 61
- D. 101
Which of the following processes occur during fractional distillation of petroleum?
- A. Condensation and diffusion
- B. Diffusion and evaporation
- C. Diffusion and sublimation
- D. Evaporation and condensation
Which of the following oxides is amphoteric?
- A. Carbon(II) oxide
- B. Nitrogen(IV) oxide
- C. Lead(II) oxide
- D. Calcium oxide
Consider the following table
| Substitute | Meltig point / ºC | Boiling point / ºC |
| P | – 78 | -25 |
| Q | – 8 | 40 |
| R | – 6 | 150 |
| S | 44 | 280 |
Which of the substances is a liquid at room temperature and rapidly evaporates on exposure to air?
- A. P
- B. Q
- C. R
- D. S