Calculate the pH of 0·05 M NaCN solution.
Given: Dissociation constant of HCN 6·2 x 10^-10 .

Calculate the e.m.f. of the cell having the reaction:

Zn Cu2+ Zn2+ Cu
where 5 x M
2 x M
The standard potentials are
E°Cu2+/Cu 0·337 V
E°Zn2+/zn =-0·763 V

Explain the principle and working of controlled potential coulometry. How can a sample solution of brass containing Zn2+ and Pb2+ be analysed by this method?

Define molar conductivity. The conductivity of 0·1 M HCl is 0·0394 . What is the molar conductivity of this solution?

Explain the following terms

Reference Electrodes

Indicator Electrodes

Write Ilkovic equation and explain all the terms. How is it used for the determination of trace metal ions

Explain briefly the solid state membrane electrodes. Describe their applications in Analytical Chemistry.

Discuss the various factors affecting the conductance of a solution.

Define any two of the following terms with the help of a suitable diagram:

Maxima Suppressor

Catalytic Current

Kinetic Current

Migration Current and its Elimination

Voltammetry

Explain the different types of titration curves obtained in amperometry giving a suitable example in each case.

Write the advantages of coulometric methods over electrogravimetric methods.

Explain briefly the principle of anodic stripping voltammetry. How is this technique used for the determination of trace metal IOns in environmental samples?

Explain the principle of cyclic voltammetry. Why has CV been recognized as the most versatile electroanalytical technique

Explain the basic principle of thermogravimetry. How is this technique used for the analysis of copper-silver alloy?

Compare the neutron activation analysis and isotope dilution techniques for trace element determination.

Complete the following nuclear reactions:

10B n .... a

20Ne 136Ba 150Dy ....

.... 2H 22Na a

130Te 2H 131I+ ....

241Am .... 243Bk 2n

Compare the basic principles of DTA and DSC techniques.

Explain the use of DTA in the identification of minerals.

Compare the potentiometric and thermometric titration curves for the titration of HCI and H3B03 with NaOH solution.

Explain the procedure for estimating the purity of a compound which melts during DSC melting endotherm.

1·0 mg of labelled naphthalene with an activity of 1,00,000 cpm is added to a 10·00 g sample of coal tar. After an elaborate series of separations, 0.0300 g of pure naphthalene is recovered. It is found to have an activity of 4,320 cpm. What is the percentage of naphthalene_ in the same?

What are the various sources of neutrons used in activation technique?

Explain briefly the theory of neutron activation analysis (NAA). How is it used for the determination of an element in a sample?

Explain how molar and equivalent conductivities of an electrolyte are related to each other.