Chemistry Laboratory II

Physical Chemistry                                                                                                    (30 Hours)

Minor Experiment                                                                                                     

1. Determination of heat capacity of calorimeter for different volumes.
2. Measurement of pH of different solutions like aerated drinks, fruit juices, shampoos and soaps (use dilute solutions of soaps and shampoos to prevent damage to the glass electrode) using pH-meter.

Major Experiments                                                                                                   

1. Determination of enthalpy of neutralization of hydrochloric acid with sodium hydroxide.

2. Determination of enthalpy of ionization of acetic acid.

3. Determination of integral enthalpy of solution of salts (KNO₃, NH₄Cl).

4. Determination of enthalpy of hydration of copper sulphate.

5. Study of the solubility of benzoic acid in water at different temperatures and determination of ΔH.

6. Preparation and measurement of the pH of the following buffer solutions and comparison with theoretical values

(i) Sodium acetate-acetic acid

(ii) Ammonium chloride-ammonium hydroxide

Organic Chemistry                                                                                                     (30 Hours)

1. Purification of organic compounds by crystallization (from water and alcohol) and distillation.

2. Criteria of purity: Determination of melting and boiling points.

3. Preparations: Mechanism of various reactions involved to be discussed. Recrystallisation, determination of melting point and calculation of quantitative yields to be done.

(a) Bromination of phenol/aniline

(b) Benzoylation of amines/phenols

(c) Oxime and 2,4-dinitrophenylhydrazone of aldehyde/ketone

Any other experiment related to above topics may also be carried out in the lab.

Scheme of Examination

The duration of examination will be 4 hrs.

The following exercises will be set in the examinations

Organic Synthesis                                                                      20 marks    

Physical Chemistry – Minor                                                        10 marks    

Physical Chemistry – Major                                                        28 marks

Viva                                                                                         12 marks

Total                                                                                 70 marks

1.Organic Synthesis

This exercise carries 20 marks. 4 marks out of 20 are reserved for neat, methodical and systematic working. The exercise amongst the candidates will be allotted by lot.

The yield, purity, crystallization and recording of M. pt. and proper presentation of the compound shall be taken into account while awarding marks.

2.Physical Chemistry Experiment:

Minor experiment

The exercise carries 10 marks. One minor experiment by lot will be given to perform. 3 marks shall be awarded for preparatory work, setting up of an apparatus, neat and methodical work.

07 marks will be awarded for correct observation, use of correct formula, calculation and result within permissible limits as follows:

• Theory and procedure                                                               2 marks
• Correct observation and proper recording                                   2 marks
• Use of correct formula and calculation                                        2 marks
•  Result                                                                                      1 marks

Major experiment

The exercise carries 28 marks. One major experiment by lot will be given to perform. 4 marks shall be awarded for preparatory work, setting up of an apparatus, neat and methodical work.

24 marks will be awarded for correct observation, use of correct formula, calculation and result within permissible limits as follows:

• Theory and procedure                                                               6 marks
• Correct observation and proper recording                                   6 marks
• Use of correct formula and calculation                                        6 marks
• Result                                                                                       6 marks

The permissible limit will be decided by the examiner as it varies with the nature of the experiment.

3.Viva

Oral questions shall generally be asked over the work assigned to the candidate. The purpose is to find out as to what extent the candidate has understood the basic principles.