Chemistry Laboratory II

Physical Chemistry                                                                                                    (30 Hours)

pH Measurement Experiment                                                                                                          

1. 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.
2. 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

  3.  To determine the strength of a strong acid or strong base using pH-metric titration.

  4. To determine the strength and dissociation constant (pKa) of a weak acid or weak base using pH-metric titration.

Thermochemistry Experiments (any five)                                                                                                     

1. Determination of heat capacity of calorimeter for different volumes.

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

3. Determination of enthalpy of ionization of acetic acid.

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

5. Determination of enthalpy of hydration of copper sulphate.

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

Organic Chemistry                                                                                                     (30 Hours)

Organic Synthesis

Synthesize following organic compounds, purify them through recrystallization and distillation, determine melting point and calculate quantitative yields. Also, understand the reaction mechanisms involved.

(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 – pH measuerment                                       19 marks

Physical Chemistry – Thermochemistry                                      19 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 melting point and proper presentation of the compound shall be taken into account while awarding marks.

2.Physical Chemistry Experiment:

The exercise carries 19 marks each. Two experiments by lottery will be given to perform. 10 marks shall be awarded for preparatory work, setting up of an apparatus, neat and methodical work.

09 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                                 3 marks
• Use of correct formula and calculation                                      2 marks
•  Result                                                                                      2 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.