Waec Chemistry Past Questions For Year 1993
Question 26
Which of the following compounds of tin is a strong reducing agent?
- A. SnCI2
- B. SnCI4
- C. SnO2
- D. SnH4
- E. Sn(OH)2
Question 27
When the trioxonitrate (IV) salt of an alkali metal Y is heated, the formula of the residue is
- A. Y2O
- B. YNO2
- C. Y2O3
- D. Y (NO2)2
- E. YO2
Question 28
Zinc displaces copper from an aqueous solution of copper (ll) salt because
- A. copper is a transition element
- B. copper is a moderately reactive metal
- C. Zinc and copper have reducing prperties
- D. zinc is more reactive than copper
- E. zinc reacts with both acids and alkalis
Question 29
When ammonium chloride is dissolved in water in a test tube, the tube feels colder showing that
- A. the solution is unsaturated
- B. sublimation has ocurred
- C. ammonia gas is evolved
- D. the process is endothermic
- E. condensation has occurred
Question 30
The product of the reaction between ethanol and excess acidified K2Cr2O2 is
- A. ethanal
- B. ethylethanoate
- C. ethanoic acid
- D. ethyne
- E. ethanedioic acid
