Question 2
D is a mixture of two inorganic salts. The following tests were carried out on D. Complete the table.
Observation
In part (a), majority of the candidates could not write the correct inference when substance D was heated.
In part (b), majority of the candidates could not write the inference when brown ring test was formed.
In part (c), majority of the candidates could not write correct observation when a portion of the solution in (b)(i) reacted with sodium hydroxide solution.
In part (d), few candidates were able to write the observations and inference when a portion of the solution reacted with dilute HNO3, AgNO3 and NH3.
The expected answers are shown in the table:
