GUIDELINES ON ANSWERING QUESTIONS IN CHEMISTRY PAPER 2
GUIDELINES ON ANSWERING STRUCTURED QUESTION
1. General
(a) As with other subjects, you should read all questions carefully and circle all important key words.
(b) Answers can be short but they must be precise and complete.
(c) The space provided for your answer gives an indication as to ‘how long’ the answer should be.
(d) Always look at the marks allotted for each question as a guide to how many points you should give.
2. Answers must be PRECISE.
* Need not write in complete sentence but your answer must be PRECISE. Example:
State the conversion of energy that occurs during the electrolysis.
State the conversion of energy that occurs during the electrolysis.
Answer:
/ The energy conversion that occurs during electrolysis is from electrical energy to chemical energy.
/ From electrical energy to chemical energy.
* Do not give answers that are not related to the need of the question.
* Read the question carefully and underline/circle important information or keywords.
Example 1:
State the observation(s). State what you experienced with your five senses only. [see, hear, smell, touch, taste].
| Incorrect observation | Correct observation |
| Chlorine gas released. | Effervescence/Gas bubbles released/ Light green gas given out. |
| Copper formed. | Brown solid deposited. [Brown deposits] |
| Deflection of the galvanometer | Deflection of the galvanometer needle. |
Example 2
Write the formula for the product formed between sodium and oxygen.
Answer:
X Na + O2 --> Na2O / Na2O X 4Na + O2 --> 2Na2O
Example 3
Write the ionic equation for the reaction between dilute hydrochloric acid and aqueous sodium hydroxide. Answer:
X HCl + NaOH è NaCl + H2O / H+ + OH– è H2O X 2H+ + 2OH– è 2H2O
Example 4
Given equation of reaction: 4Na + O2 è 2Na2O
Name the product formed.
X Na2O / sodium oxide.
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