Chemistry 2019 Past Questions | WAEC
31. If a catalyst is added to a system, the temperature and the pressure remain constant, there would be no effect on the?
- A. activation energy of the reaction
- B. rate of the reaction
- C. rate of the reverse reaction
- D. heat of reaction
32. consider the following reaction equation: 2NH3 + 3Cl2→ N2 + 6HCl.
NH3 is acting as?
- A. a reducing agent
- B. a dehydrating agent
- C. a drying agent
- D. an oxidizing agent
33. The oxidation of chromium in Cr22O7/−27)\(−2?
- A. +4
- B. +5
- C. +6
- D. +7
34. The process by which alkanoic acid reacts reversibly with alkanols is known as?
- A. saponification
- B. esterification
- C. carboxylation
- D. halogenation
35. If the oxidation potential of Mg and Al are +2.37 volts and + 1.66 volts respectively, then the Mg would?
- A. not replace Al
- B. be replaced by Al
- C. remain in the solution
- D. replace Al
36. consider the reaction represented by the following equation: 2SO2+ O2⇌ 2SO3
A decrease in the pressure of the reaction would
- A. decrease in the concentration of SO2
- B. have no effect on the reaction
- C. shift the equilibrium position to the left
- D. shift the equilibrium position to the right
37. In a mixture of gases which do not react chemically together, the pressure of the individual gas is?
- A. atmospheric pressure
- B. vapor pressure
- C. total pressure
- D. partial pressure
38. Biotechnology is applied in the?
- A. treatment of sewage
- B. treatment of water
- C. purification of chemicals
- D. purification of metals
39. which of the following organic compounds has the lowest boiling point?
- A. C6H14
- B. C5H12
- C. C4H10
- D. ( CH3 )3
40. Consider the following reaction represented by the following equation: C2H2H2→H2X H2→H2)X and Y respectively are?
- A. ethane and ethene
- B. ethene and ethane
- C. ethyne and ethene
- D. ethane and ethyne
41. Which of the following substances can be classified as heavy chemicals?
- A. CaOCl2
- B. H2SO4
- C. AgNO3
- D. CaO
42. in Boyle’s law?
- A. T is constant, P varies directly with V
- B. P is constant, V varies inversely with T
- C. V is constant, P varies directly with T
- D. T is constant, V varies inversely with P
43. Which of the following apparatus is NOT used in volumetric analysis?
- A. Pipette
- B. Burette
- C. Desiccator
- D. conical flask
44. One of the deductions from Rutherford’s alpha particle scattering experiment is that?
- A. electrons are negatively charged
- B. electrons have a negligible mass
- C. nuclei of atoms are positively charged
- D. protons are positively charged
45. The atoms of 64/29 CU and 65/30Zn have the same number of?
- A. nucleon
- B. electrons
- C. neutrons
- D. protons
