PUC Science 2nd PUC Class 12 - Karnataka Board PUC Question Bank Solutions for Chemistry

H₂S, a toxic gas with rotten egg like smell, is used for the qualitative analysis. If the solubility of H₂S in water at STP is 0.195 m, calculate Henry’s law constant.

Henry’s law constant for CO₂ in water is 1.67 × 10⁸ Pa at 298 K. Calculate the quantity of CO₂ in 500 mL of soda water when packed under 2.5 atm CO₂ pressure at 298 K.

The partial pressure of ethane over a solution containing 6.56 × 10⁻³ g of ethane is 1 bar. If the solution contains 5.00 × 10⁻² g of ethane, then what shall be the partial pressure of the gas?

Based on solute-solvent interactions, arrange the following in order of increasing solubility in n-octane and explain.

Cyclohexane, KCl, CH₃OH, CH₃CN

Henry’s law constant for the molality of methane in benzene at 298 K is 4.27 × 10⁵ mm Hg. Calculate the solubility of methane in benzene at 298 K under 760 mm Hg.

The air is a mixture of a number of gases. The major components are oxygen and nitrogen with approximate proportion of 20% is to 79% by volume at 298 K. The water is in equilibrium with air at a pressure of 10 atm. At 298 K if the Henry’s law constants for oxygen and nitrogen are 3.30 × 10⁷ mm and 6.51 × 10⁷ mm respectively, calculate the composition of these gases in water.

Calculate the potential of hydrogen electrode in contact with a solution whose pH is 10.

Calculate the emf of the cell in which the following reaction takes place:

\[\ce{Ni_{(s)} + 2Ag+ (0.002 M) -> Ni^{2+} (0.160 M) + 2Ag_{(s)}}\]

Given that \[\ce{E^\circ_{cell}}\] = 1.05 V

A first order reaction has a rate constant 1.15 × 10⁻³ s⁻¹. How long will 5 g of this reactant take to reduce to 3 g?

Time required to decompose SO₂Cl₂ to half of its initial amount is 60 minutes. If the decomposition is a first order reaction, calculate the rate constant of the reaction.

The following data were obtained during the first order thermal decomposition of SO₂Cl₂ at a constant volume.

\[\ce{SO2Cl2_{(g)} -> SO2_{(g)} + Cl2_{(g)}}\]

In a pseudo first order hydrolysis of ester in water, the following results were obtained:

Calculate the average rate of reaction between the time interval 30 to 60 seconds.

The rate constant for a first order reaction is 60 s⁻¹. How much time will it take to reduce the initial concentration of the reactant to its `1/16`th value?

For the decomposition of azoisopropane to hexane and nitrogen at 543 K, the following data are obtained.

Calculate the rate constant.

The time required for 10% completion of a first order reaction at 298 K is equal to that required for its 25% completion at 308 K. If the value of A is 4 × 10¹⁰ s⁻¹. Calculate k at 318 K and E_a.

What is the significance of leaching in the extraction of aluminium?

How can you separate alumina from silica in a bauxite ore associated with silica? Give equations, if any.

How is leaching carried out in case of low grade copper ores?

Indicate the type of isomerism exhibited by the following complex and draw the structure for the isomer: 

K[Cr(H₂O)₂(C₂O₄)₂]

Indicate the type of isomerism exhibited by the following complex and draw the structure for the isomer:

[Co(en)₃]Cl₃