Osmania University (OU) 2006-1st Year B.Pharm 2nd st semester Pharmaceutical Analysis Main, - Question Paper

2nd year first semester Pharmaceutical Analysis Main, Dec 2006

1. (a) What is an error? Classify the errors encountered in chemical analysis.

(b) Write about the various kinds of systematic errors and their minimization.

OR

(c) describe primary standard and secondary standard substances. provide the prerequisites for a primary standard.

(d) compute and compare the accuracy and precision of bazra protein. Mean value estimated by methods A and B, with samples of size five and 10:

S.No. Sample size Mean protein Content
Method A Method B

one five 11.5 12.0

two 10 11.8 12.1

actual value of bazra protein is 12.10


2. (a) discuss various theories of acid-base indicators. Add a note on "Mixed indicators"

(b) Write notes on the following:
(i) Role of buffers in pharmacy
(ii) Salt hydrolysis

OR

(c) define the reaction and procedure involved in the assay of aspirin.

(d) How will you prepare and standardize a decinormal solution of sodium hydroxide?


3. (a) explain the principle and various steps involved in gravimetric analysis.

(b) discuss red ox titrations in detail.

OR

(c) How will you prepare and standardize 0.1N Iodine solution?

(d) Write about co-precipitation and post-precipitation in gravimetric analysis?


4. (a) explain the principle and procedure for the assay of carbon dioxide as per B.P.

(b) A sample of pure sodium carbonate weighing 0.3542 gms is dissolved in water and titrated with a solution of HCl. A quantity of 30.23 ml is needed to reach the methyl orange end point. Reaction being Na2CO3 + 2HCl ? 2NaCl + H2O + CO2. compute the molarity of acid.

(c) compute the normality of 10 mill moles of KMnO4 in 200 ml of solution.

OR

(d) provide the description and working of Hempes apparatus with a neat diagram.

(e) 1.35 gms of ferrous sulphate are added to a flask containing 20 ml of dilute sulphuric acid. On titration of the above solution with 0.1N permanganate solution, needed 45.5 ml for complete reaction. What i the % purity of ferrous sulphate?


5. (a) describe the terms mole and discuss about Avogadro’s number.

(b) Write the mass balance formula of the subsequent equations:
(i) Ammonium hydroxide + Sulphuric acid ? Ammonium sulphate + Water
(ii) Sodium carbonate + Hydrochloric acid ? Sodium chloride + Water + Carbon dioxide.

(c) describe the terms theoretical yield and percentage yield.

OR

(d) describe the terms molecular formula and empirical formula with suitable examples.

(e) compute he percentage composition of the elements of the subsequent compounds:
(i) Potassium dichromate.
(ii) Potassium permanganate.
(iii) Copper sulphate.
(iv) Mangonous sulphate.

Earning:   Approval pending.