1.
Write down the equation of state for van der Waals gases with symbolic significances and find the dimension of van der Waals constants.


Helium gas at 500 K expands adiabatically and reversibly to double its volume. Find the final temperature of the gas in degree Celsius. (Assume that He gas behaves ideally)



Explain the Arrhenius theory of acids and bases with examples.




List the factors which influence the efficiency of Carnot engine. How?



The effect of temperature on the value of dimerization constant is negative. Justify with the help of van't Hoff equation isobar


Derive the integrated rate equation for a zero-order reaction. Give one example of zero-order reaction.

What is van't Hoff factor of a solution? Derive its relation with degree of Ionization of solute in a solution.

Define "molar extinction coefficient (ε)". What is its unit? What factors can influence its value?



Show that the unit of magnetic dipole moment is A m^2
which is also equivalent to J Here T stands for tesla, the unit of magnetic field strength.


Why is surface tension of liquid ethanol greater than liquid dimethyl ether though both have same molecular mass?

Explain why H20 is a liquid while H2S is a gas at room temperature.


Show that y is an eigenfunction of the operator

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What is the eigenvalue?

Which of the following transitions are allowed in the normal electronic emission spectrum of an atom? Give reason(s)


2s 1s

2p ls

3d 2p

3d 4s

5p 3S





2. Derive
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(symbols have their usual meanings) . Find the expression of(Cp-Cvl for a gas obeying equation of state.P(v-nb) nRT




3. 18·0 g of liquid water vaporizes at 1 bar and 373 K. Calculate ΔU, ΔH, ΔS, ΔA, ΔG (in SI units) for this process. Given, latent heat of vaporization of liquid water at 1 bar and 373 K is 540 cal

4. Derive Gibbs-Duhem equations for a mixture system at constant pressure and temperature.


5. O·1 kg mol^-1 aqueous solutions of two 1-1 electrolytes A and B freeze at 0·360 °C and 0·208 respectively. Calculate Hoff factor of each
solution and the degrees of ionization or A and B in their solution. Suggest the nature of electrolytes. Given.

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6. What will be the value of absorbance of transparent liquid water with respect to visible light Give reason.

Write a note on 'photosensitized reaction' with example of photosynthesis.



7. Define 'most probable speed' of a molecule in gaseous, system. Derive its expression using the following speed distribution equation

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(Symbols have their usual meanings.)


Find the pH of aqueous caustic soda solution.


8. Show that for a first-order reaction. the time required for completion of 99·9% reaction is ten times of its half-life period.


The standard reduction potential value of electrode is negative and of electrode is positive.What will be the cell reaction, if we couple two
electrodes to form a galvanic cell? Give reason(s)in support of your answer.



9. A spherical water drop of radius 10 mm is sprayed into a million of droplets of same size. Find the work done in this process. Given that γ(surface tension) of water at the
experimental temperature is 72.0 dyne cm^-1.


10. Sliver crystallizes in an f.c.c. structure with a unit cell length of 408·6 pm. UsingBragg equation, calculate the first-order diffraction angle for 1 plane using X-ray of wavelength 154·433 pm.

The force constant of a harmonic oscillator of reduced mass 1.5 x 10^-27 kg is 10 N Calculate its zero-point energy.







11.(a) Derive

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(symbols have their usual meanings) using thermodynamic
concept of chemical potential. Mention all assumptions and approximations at proper places.

The temperature of a hot cup of tea decreases spontaneously in a closed system at constant pressure without loosing its mass. So for this change

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Justify with reasons.


12.(a) Discuss hypochromic effect in connection to UV spectra.


The quantum yield for the reaction, H2 at λ 250 nm is 2·0. If 3070 J of light is absorbed, find the number of moles or HI decomposed.

What is indicated by peak area in PMR spectrum? How many peaks will be observed in PMR spectrum or pure ethanol? What will be their peak area ratio? Explain with diagram, if possible.



13. Write down Debye-Huckel limiting equation with symbolic significances and units. Find the ionic strength of 0·01 mol^-1. aqueous solution of potassium ferrocyanide.

The average lifetime of phosphorescence is higher than fluorescence. Explain with Jablonsky diagram.

Hydrogen nucleus is NMR active but the nuclei of

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and are inactive. Explain why.




14. Derive Langmuir adsorption isotherm expression for the process
O3

Calculate the equilibrium constant, K for this process when the coverage of O is 0.50 at
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The wave number or J 0 to J 1 transition for pure rotational spectrum of
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Assuming the molecule u a rigid rotor, calculate its
moment of inertia in kg m^2 and equilibrium bond length in m.


15. Derive the expressions of critical constants

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for van der Waals gases



In an aqueous solution of HCl, the transport number of ion is abnormally higher than Cl- ion. Explain why.


Find the units of A and Ea(in SI units) using the equation,

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k is the zero-order rate constant.