ISC 2015 Chemistry Practical Question Paper for Class 12

About this paper

This is ISC Class 12 Chemistry Paper 2 (Practical), code 862B, from the 2015 board examination. It runs for three hours plus fifteen minutes of reading time, and the four questions carry 30 marks. Question 1 is a redox titration of impure potassium manganate(VII), 3.5 g per litre, against oxalic acid dihydrate, 6.5 g per litre, and it asks for the percentage purity of the permanganate. Question 2 is the identification of an organic compound and of a second sample as a carbohydrate or a protein. Question 3 is the qualitative analysis of a salt with two anions and two cations, without a qualitative analysis table. Question 4 is the project and the practical file. Mathematical tables are provided. This copy has the questions only.

Exam

ISC Class 12

Subject

Chemistry Practical

Year

2015

Paper code

862B

Maximum marks

30

Time allowed

3 hours + 15 min reading

Questions

4

Pages

5

Answers included

No, questions only

Paper pattern

• Question 1

  8 marks

  Redox titration of impure potassium manganate(VII) against oxalic acid, including percentage purity

• Question 2

  5 marks

  Identification of an organic compound, and of a second sample as carbohydrate or protein

• Question 3

  7 marks

  Qualitative analysis of substance C-15, which contains two anions and two cations

• Question 4

  10 marks

  Project (7 marks) and chemistry practical file (3 marks)

Topics covered

• Redox titration
• Potassium permanganate
• Oxalic acid
• Organic compound identification
• Carbohydrates and proteins
• Qualitative analysis of anions
• Qualitative analysis of cations

Questions from this paper

1. C-10 is an impure sample of potassium manganate(VII), KMnO4, at 3.5 g per litre, and C-11 is oxalic acid, H2C2O4·2H2O, at 6.5 g per litre. Find the molarity of each solution, the strength of the permanganate in grams per litre, and the percentage purity of the sample.
2. Identify organic compound C-13 from its behaviour with Tollen's reagent, with freshly prepared pyrogallol and concentrated hydrochloric acid, and with resorcinol and concentrated sulphuric acid.
3. Substance C-14 is either a carbohydrate or a protein. Use the α-naphthol test, the lead acetate test and the copper sulphate–sodium hydroxide test to decide which it is.
4. Analyse substance C-15 qualitatively. It contains two anions and two cations, and a qualitative analysis booklet or table may not be used.