31. Potassium Chloride solid does not conduct electricity because
- A. it is a covalent compound
- B. strong cohesive forces make its ions immobile
- C. strong cohesive force makes its molecule immobile
- D. each of potassium and chlorine structures contain noble gas structure
32. When water was added to a white anhydrous substance X, the colour changed to blue. X is
- A. \(CuSO_{4}\)
- B. \(FeSO_{4}\)
- C. \(Na_{2}SO_{4}\)
- D. \(PbSO_{4}\)
33. Solubility curve can be used in the determination of the
- A. amount of crystals formed
- B. amount of solvent that can be recovered
- C. amount of solid drugs in a given solution
- D. temperature of the solution
34. If 0.2g of a salt is required to saturate 200\(cm^{3}\) of water at room temperature, what is the solubility of the salt?
- A. 0.2\(gdm^{-3}\)
- B. 1.0\(gdm^{-3}\)
- C. 2.0\(gdm^{-3}\)
- D. 5.0\(gdm^{-3}\)
35. The property of a chemical reaction that is affected by the presence of a catalyst is
- A. activation energy
- B. free energy
- C. equilibrium position
- D. enthalpy change
36. Soluble salts can be prepared by the following methods except
- A. neutralization
- B. reaction of an acid with trioxocarbonate(IV) salt
- C. double decomposition
- D. reaction of an acid with electropositive metals
37. Chemical reactions occurs when the colliding reactants have energy that is
- A. less than the activation energy
- B. greater than the activation energy
- C. greater than the energy of the product
- D. less than the energy of effective collision
38. The common feature of reactions at the anode is that
- A. electrons are consumed
- B. ions are reduced
- C. oxidation is involved
- D. the electrode dissolves
39. Consider the following reaction equation: \(2NO_{(g)} + O_{{2}{(g)}} \to 2NO_{{2}{(g)}}\). What is the change in the oxidation number of nitrogen?
- A. +2 to 0
- B. +2 to -2
- C. +2 to +4
- D. +4 to +2
40. Which of the following factors characterize members of the same homologous series?
- A. The chemical property change gradually throughout the series
- B. physical properties of members are similar
- C. They have the same molecular formular
- D. Successive members undergo changes in molecular formula by CH2
