HSC Science (Computer Science) इयत्ता १२ वी - Maharashtra State Board Question Bank Solutions for Chemistry

The rate constant of a reaction at 500°C is 1.6 × 10³ M⁻¹ s⁻¹. What is the frequency factor of the reaction if its activation energy is 56 kJ/mol?

The rate constant for the first-order reaction is given by log₁₀ k = 14.34 – 1.25 × 10⁴ T. Calculate activation energy of the reaction.

Solve

What fraction of molecules in a gas at 300 K collide with an energy equal to the activation energy of 50 kJ/mol?

How will you determine activation energy from rate constants at two different temperatures?

Explain with the help of the Arrhenius equation, how do the rate of reaction changes with activation energy.

Write uses of sulphur.

0.01 m aqueous formic acid solution freezes at – 0.021°C. Calculate its degree of dissociation, K_f = 1.86 K kg mol^–1.

Write the correct condition for spontaneity in terms of Gibbs energy.

Draw labelled diagram of H₂ – O₂ fuel cell.

Write two applications of fuel cells.

Identify whether the following pair have larger entropy or not. If yes then Why?

He(g) in a volume of 1 L or He(g) in a volume of 5 L both at 25°C.

Identify whether the following pair have a larger entropy or not. If yes then Why?

O₂{g) at 1 atm or O₂(g) at 10 atm both at the same temperature.

Identify whether the following pair have a larger entropy or not. If yes then Why?

C₂H₅OH(l) or C₂H₅OH(g)

Write modification of expressions of colligative properties with the help of van't Hoff factor.

Write the relationship between Gibbs energy change for a process and total entropy change of system and surroundings.

Calculate the van't Hoff factor assuming the complete dissociation of NaBr in its aqueous solution.

What is a spontaneous process? What are its characteristics?

Calculate ΔT_b and boiling point of 0.05 m aqueous solution of glucose. (Given: K_b = 0.52 K m⁻¹).

Write the mathematical equation between reaction rate constant and its activation energy.

Calculate ΔG for ΔH = − 110 kJ, ΔS = + 40 J K⁻¹ at 400 K.