HSC Science (Computer Science) 12th Standard Board Exam - Maharashtra State Board Important Questions

Describe, with the help of a circuit diagram, the working of Zener diode as a voltage regulator.

Write differences.

Tribal community and Rural Community

Explain the term osmosis.

Explain the term osmosis.

Calculate the e.m.f. of the following cell at 298 K:

Fe(s) | Fe²⁺ (0.001 M) | | H⁺ (0.01 M) | H₂(g) (1 bar) | Pt(s)

Given that \[\ce{E^0_{cell}}\] = 0.44 V

[log 2 = 0.3010, log 3 = 0.4771, log 10 = 1]

Calculate emf of the following cell at 25°C:

\[\ce{Sn/Sn^2+ (0.001 M) || H+ (0.01 M) | H2_{(g)} (1 bar) | Pt_{(s)}}\]

Given: \[\ce{E^\circ(Sn^2+/sn) = -0.14 V, E^\circ H+/H2 = 0.00 V (log 10 = 1)}\]

Define the Standard enthalpy of combustion.

For a reaction A + B ⟶ P, the rate is given by

Rate = k [A] [B]²

How is the rate of reaction affected if the concentration of B is doubled?

For a reaction A + B ⟶ P, the rate is given by

Rate = k [A] [B]²

What is the overall order of reaction if A is present in large excess?

Distinguish between Order and Molecularity of reaction.

Explain pseudo-first-order reaction with an example.

Describe the manufacturing of H₂SO₄ by the contact process.

Elements of group 16 have lower ionization enthalpy values compared to those of group 15 elements. Explain why?

Distinguish between lanthanoid and actinoids.

[NiCl₄]²⁻ is paramagnetic, while [Ni(CO)₄] is diamagnetic, though both are tetrahedral. Why? (Atomic number of Ni = 28)

Distinguish between lanthanoid and actinoids.

Explain the concept of Macro economics and its features.

Distinguish Between:

Partial equilibrium and General equilibrium

State and explain the ‘law of demand’ with its exceptions.

What is the elasticity of demand?