HSC Science (General) इयत्ता १२ वी - Maharashtra State Board Important Questions

Calculate the work done in the following reaction at 50°C. State whether work is done on the system or by the system.
`"SO"_2("g") + 1/2"O"_(2("g")) rightarrow "SO"_(3("g"))`

The standard enthalpy of combustion of formaldehyde Δ₀H⁰ = -571 kJ. How much heat will be evolved in the formation of 22 g of CO₂?

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?

Choose the most correct answer :

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.

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 ______.

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.

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

Distinguish between strong electrolyte and weak electrolyte.

The pH of 0.001 M HCl solution is ______.

Calculate the pH of buffer solution composed of 0.01 M weak base BOH and 0.02 M of its salt BA. [K_b = 1.8 × 10^–5 for weak base]