Physical Chemistry Answers

The fundamental and 1st overtone of a molecule are found 2886 (1/cm) and 5668 (1/cm). Calculate equilibrium oscillation wave no. and the anharmonicity constant

Dry air is passed through a solution containing 10 g of the solute in 90 g of water and then through pure water. The loss in weight of solution is 2.5g and that of pure solvent is 0.05g. The molecular weight of the solute is

4moles of an equimolar mixture of cl2and N2 are added to a vessel containing 1 mole of PCl5,2moles of PCl3,and 3 moles of Cl2 at equilibrium,the mole fraction of PCl5 at equilibrium will be?

Kp for N2O4<------>2NO2 at equilibrium pressure 3Po is 0.5Po on halving the volume of container equilibrium is distributed the new equilibrium pressure will be?

When an electron in an atom of element X relaxes from the third excited state to the ground state light is emitted. The light is found to have an energy of 1260 kJ/mol. What is the wavelength, in nm (to 1 decimal place, input value only), of the light?

Calculate the mole fraction of each component in a methanol-ethanol mixture over which the equilibrium vapour pressure is 6.0 kPa. Assume that the mixture is ideal.
(Vapour pressure of pure methanol is 8.9 kPa; vapour pressure of pure ethanol is 4.0 kPa)

Oxidation:Br2_ BrO3-
Reduction: Br2_ Br-

If you have a flexible, closed container at room temperature in normal air (initial temperature = 298 K, constant pressure = 1 atm, constant n) and you see grow to 4 times its original volume, what must’ve happened?

Buffer solutions are important in biological systems and in industry to maintain almost
constant pH values.
In the human body, one of the important buffer systems in blood involves the
hydrogencarbonate ion (HCO3-) and carbonic acid (H2CO3) which is formed when
carbon dioxide dissolves in water.
(i) Use the following equation to explain how this buffer maintains a constant pH of
7.41 even if a small amount of acid enters the bloodstream.

H2CO3 (aq) ⇄ H+(aq) + HCO3- (aq)

(ii) Provide a clear explanation in relation to the Henderson-Hasselbach equation or appropriate calculations of pH based on the above equation.

Analyse how conditions which are likely to be present in a given industrial situation (e.g. oil-platform, industrial boilers) differ from ideal conditions and are likely to affect predictions of corrosion tendency based on standard reduction potentials.