Candidates’ Name: …………………………………..…………………………..…………………..

Signature: …………………..………………………

(Do not write your school / Center name or Number anywhere on this booklet)

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CHEMISTRY

Paper 3 July / Aug 2024 2 ½ HOURS

Uganda Certificate Of Education CHEMISTRY

Paper 3

TIME: 2 hours 30 minutes

CONFIDENTIAL

Great care should be taken that the information given below does not reach the candidates either directly or indirectly.

INSTRUCTIONS FOR PREPARING CHEMICALS AND APPARATUS

The candidates will be allowed to write out a detailed description of the apparatus. The teacher responsible for preparing the apparatus must give details (on the report form attached) about some of the items or apparatus he /she has supplied. The form should be signed by the invigilator, teacher responsible for preparing the apparatus and the Head teacher.

NB: The Head teacher must ensure that the teacher responsible for preparing the apparatus hands in his/ her trial results, properly sealed in a separate envelope and firmly fastened (attached) to the candidates’ scripts envelope(s).

1. The description of the reagents and chemicals specified below does not necessarily correspond with the description in the question paper. Candidates must not be informed of the
2. Candidates are not allowed to use reference books (i.e. text books, booklets on qualitative analysis etc.) during examination.
3. In addition to the fittings and substances ordinarily contained in a chemistry laboratory, each candidate will require:

• 50cm³ measuring cylinder (or 100cm³ measuring cylinder)

• 10cm³ measuring cylinder

• Plastic beaker (or Plastic cup)

• Stop clock (or Stop watch)

• A thermometer

• 100cm³ of KA1

• 100cm³ of KA2

NB: KA1 is a 1.5M sodium hydroxide solution KA2 is a 2.0M sulphuric acid.

INSTRUCTIONS TO CANDIDATES

This paper consists of one compulsory item.

Answers to this item are to be written in the spaces provided in this booklet.

Use blue or black ink All working must be clearly shown. A Graph paper will be provided

Mathematical tables and silent non-programmable scientific calculators may be used. You are not allowed to use reference books.

Candidates are advised to carefully read the item, make sure they have all the apparatus and chemicals they may need and then plan appropriately before starting. .

FOR EXAMINER’S USE ONLY

Item 1

In a local village around Sukuru subcounty, in Tororo district, the water discharged into the valley dams from small industries contains traces of sulphuric acid which is unfavourable to the fresh water fish. The industry managers have been advised to use solution KA1 to neutralize the acid in the water without affecting the life of fish.

This is because the reaction between KA1 and sulphuric acid may produce amounts of heat which is unfavourable, yet fresh water fish thrives well only if the heat change of

2.47 – 2.52kJ occurs in water.

You are provided with the following; Solution KA1

Solution KA2 is a sample of the acidic fresh water. Some apparatus

Task

• Design an experiment you can use to determine the amount of heat evolved in this reaction.

• carry out the experiment you can use to determine the amount of heat evolved.

• Analyse your results and hence draw possible conclusions.

END