Question 2
F is an organic solid. Carry out the following exercises on F. Record your observations and identify any gas(es) evolved. State the conclusions you draw from the result of each test.
- Divide F into two equal portions.
- Put the first portion of F into a dry boiling tube and heat strongly.
- Put the second portion of F into a test tube and add about 10 cmX3 of dilute HNO3. (Filter if necessary).
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To about 2 cm3 portion of the resulting solution:
- add dilute NaOH in drops and then in excess;
- add dilute NH3 in drops and then in excess;
- add HCl(aq).
- From your results, identify the ions in F.
Observation
This question was well attempted by majority of the candidates and their performance was fair.
In part (a), some of the candidates did not report their observations and inferences in the acceptable format. Also, majority of them wrote wrong charges and inferences.
In part (b), majority of the candidates did not follow the instructions. Hence, they recorded wrong observations.
In part (c), majority of the candidates could not identify the ions in F.
The expected answers include:
