HSC Science (Electronics) 12th Standard Board Exam - Maharashtra State Board Important Questions for Chemistry

5 moles of helium expand isothermally and reversibly from a pressure 40 × 10^-5  N m^-2 to 4 × 10^-5 N m^-2  at 300 K. Calculate the work done, change in internal energy and heat absorbed during the expansion. (R = 8.314 J K^-1  mol^-1).

Write features of a reversible process.

A substance which shows the highest entropy is ___________.

Choose the most correct answer:

Which of the Na following is a buffer solution?

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For pH > 7 the hydronium ion concentration would be _________.

Answer the following in brief :

What are acids and bases according to Arrhenius theory?

In NaOH solution [OH^–] is 2.87 × 10^–4. Calculate the pH of the solution.

Answer the following :

Explain the relation between ionic product and solubility product to predict whether a precipitate will form when two solutions are mixed?

For a reaction \[\ce{HCl_{(aq)} + H2O_{(l)} ⇌ H3O^+_{ (aq)} + Cl^-_{ (aq)}}\]

Which of the following is a conjugate acid-base pair?

The theory which explain amphoteric nature of water is ______.

The pK_b of weak base BOH [K_b(BOH) = 1 × 10^-5] will be ______.

The solubility product of BaCl₂ is 4.0 × 10^-8. What will be its molar solubility in mol dm^-3?

Classify the following species into Lewis acids and Lewis bases.

Explain the types of buffer solutions.

Derive the equation which implies that the degree of dissociation of weak acid is inversely proportional to the square root of its concentration.

A buffer solution contains 0.3 mol dm^–3 NH₄OH (K_b = 1.8 × 10^–5) and 0.4 mol dm^–3 NH₄Cl. Calculate pOH of the solution.

The solubility of AgBr in water is 1.20 × 10^–5 mol dm^–3. Calculate the solubility product of AgBr.

Derive the equation p^H + p^OH = 14.

Distinguish between strong electrolyte and weak electrolyte.

The pH of 0.001 M HCl solution is ______.