Calculate the lattice energy (in Units kJ mol^-1) for ZnO crystal using electrostatic model and using a Born-Haber cycle. Compare the two answers and comment on any difference.

Useful data:

Medelung constant (A) = 1.6411

Born Constant () = 8

Internuclear distance (a) = 199 pm

Zn(s) + 1/2 O₂(g) → ZnO(s) H_f = - 350.5 kJ mol^-1

Zn(s) → Zn(g) H = 130.4 kJ mol^-1

Zn(g) → Zn⁺ (g) I(Zn) = 906.3 kJ mol^-1

Zn⁺(s)→Zn²⁺(g) I(Zn⁺) 1733 kJ mol^-1

1/2 O²(g) → O^-(g) H=248.5 kJ mol^-1

O(g) →0^-(g) E_A(O) = 141 kJ mol^-1

O^-(g) →0^2-(g) E_A(0^-) = -780 kJ mol^-

Describe the depositional landforms resulting from fluvial activities with the help of neat well labelled diagrams.

Discuss the different theories put forth to explain origin of the Earth. Which theory is considered as the best possible model?

Criteria for recognition of faults

Relationship of Geology with Earth Science

First ionisation energies of second period elements show that the values increase from lithium to beryllium, decrease for boron, and increase up to nitrogen, again decrease in oxygen and finally increase up to neon. Explain.

List different excitation sources used for atomic emission spectrometry. Discuss the interferences observed in flame atomic emission Spectrometry

State aufbau principle.

Write the electronic configuration of the following:

Cl, Cr, Nb

Outline the advantages of premix burner in atomic spectroscopy. Discus structure of a laminar flow flame showing various zones.

Calculate the number of vibrational degrees of freedom for ethane, C2H6, explain the fingerprint and functional group regions in IR spectrum.

Explain the transformation of Schrodinger equation from Cartesian to spherical polar coordinates and give its solution.

What are monochromators? Explain the working of prism monochromator with the help of a suitable diagram.

Arrive at the time independent Schrodinger equation for a particle.

State Beer and Lambert's law and write its mathematical expression.

Name the phenomena which can be explained using

(i) wave nature of radiation

(ii) particle nature of radiation.

Molecular spectra are band spectra whereas atomic spectra are line spectra. Explain.

Define electromagnetic radiation and state the relationship between the velocity and wavelength of an electromagnetic radiation.

Briefly explain Heisenberg uncertainty principle.

An impure sample of CaC₂O₄ . H₂O is analyzed using TGA technique. TG curve of the sample indicates the total mass change from 85 mg to 30.7 mg when this sample was heated up to 1173 K. calculate the purity of the sample.