ANSWER THE FOLLOWING QUESTIONS

(A) SALT-ESSAY

1 You are required to prepare a sample of dry copper (II) nitrate.Anda dikehendaki menyediakan satu sampel kuprum nitrat yang kering.

Describe a laboratory experiment to prepare the salt.Include these in your answer :

Name of the reactant List of apparatus Procedure Chemical equation.

Huraikan satu eksperimen yang boleh dijalankan dalam makmal untuk menyediakan satu sampel garam tersebut.Jawapan anda perlu mengandungi perkara berikut :

Nama bahan tindak balas Senarai radas Prosedur Persamaan kimia terlibat

Aras tinggi [10 marks] KBAT

2 You are required to prepare dry barium sulphate salt.Anda dikehendaki menyediakan garam barium sulfat kering.

(i) Suggest two solutions to prepare barium sulphate salt. Cadangkan dua larutan untuk menyediakan garam barium sulfat.

(ii) Describe a laboratory experiment to prepare the salt. In your description, include the chemical equation and ionic equation. Huraikan suatu eksperimen makmal untuk menyediakan garam tersebut..Huraian anda mesti mengandungi persamaan kimia dan persamaan ion.

Aras tinggi [10marks] KBAT

1.

Reactant:Metal oxide + acid salt + water

Apparatus:100 cm3 beaker,glass rod,spatula,tripod stand,wire gauze,bunsen burner,filter funnel,retort stand and clamp,evaporating dish,measuring cylinder

Materials:2 mol dm^-3 nitric acid,copper(II)oxide powder,filter paper

Procedure

1.50cm3 of 2 mol dm-3 nitric acid is measured using a meausring cylinder and poured into a beaker.

2.The nitric acid is heated carefully in the beaker.

3.Copper(II) oxide powerder is added a little at a time to the nitric acid using a spatula.The mixture is stirred well.

4.Copper(II)oxide powerder is added continuosly until some of it no longer dissolves.

5.The contents are filtered.

6.The filtrate is poured into an evaporating dish.

7.The salt solution in the evaporating dish is gently heated for evaporation to occur until it becomes saturated.

8.The hot saturated solution is cooled to room temperature for crystalisation to occur.

9.The contents are filtered to obtain the copper (II) nitrate crystals.

10.The crystals are pressed between a few pieces of filter paper to be dried.

Copper (II) oxide react with dilute nitric acid through the following chemical equation:

CuO+H2NO3 Cu(NO3)2+H20

2. (i) Barium chloride solution and Sodium sulphate solution

(ii) Apparatus: Beaker,measuring cylinder,glass rod,filter funnel,retort stand and clamp

Materials:0,5mol dm-3 barium chloride solution,0.5 mol dm-3 sodium sulphate solution,filter paper

Procedures:

1.50cm3 of 0.5 mol dm-3 barium chloride solution is poured into 50cm3 of 0.5 mol dm-3 sodium sulphate solution in a beaker.

2.The mixture is stirred with a glass rod.

3.A white precipitate of barium sulphate is formed immediately

4.The resulting mixture is then filtered.

5.The residue is rinsed with distilled water to remove impurities such as sodium chloride and others.

6.The white solid,barium sulphate is then pressed between a few pieces of filter paper to be dried.

Barium chrloide solution react with sodium sulphate solution through the following chemical equation:

BaCL +Na2SO4 BaSO4 + 2 NaCl