HomeWAECWAEC Standard for Chemistry Alternative to Practical.
September 1, 2019
WAEC Standard for Chemistry Alternative to Practical.
A is a simple salt. The following tests were carried out on A. complete the following table.
(b)(i) Name the salt A. (ii) Write the formula of A.
The following tests were carried out on a sample of an unsaturated alkanol K. Complete the following table.
Majority of the candidates responded to this question. In part (a), majority of the candidates were able to suspect Zn2+ and Al3+ correctly. However, some candidates included Pb2+ because of the gelatinous precipitate. In part (b), majority of the candidates named the salt A and wrote the formula of A. In part (c), majority of the candidates did not attempt this question. The candidates that attempted performed poorly. . The expected answers include:
(b) (i) Aluminium trioxonitrate (V) (ii) Al(NO3)3
N.B: Al3+ must have been identified in (a)(iv) to score b(i) and (ii).