HSC Science (General) १२ वीं कक्षा - Maharashtra State Board Question Bank Solutions

Classify the following molecular solids into different types: 

1. HCl
2. CO₂
3. Solid ice
4. SO₂

The molar conductivity of 0.05 M BaCl₂ solution at 25° C is 223Ω^-1 cm² mol^-1. What is its conductivity?

Define Anisotropy.

In a first-order reaction A → product, 80% of the given sample of compound decomposes in 40 min. What is the half-life period of the reaction? 

The S.I. unit of cell constant for conductivity cell is __________.

Write a preparation of phenol from cumene? What happens when phenol is heated with zinc dust? 

Draw the structures of veronal and thymine. 

Identify A and B respectively in the following reaction:
\[\ce{tert-butyl alcohol ->[20‰H2SO4][363K] A + H2O ->[HBr][H2O2] B}\]

How are the crystalline solids classified?

Answer the following in one or two sentences.

A solid is hard, brittle and electrically nonconductor. Its melt conducts electricity. What type of solid is it?

Answer the following in brief.

Distinguish between ionic solids and molecular solids

Choose the most correct answer :

The conjugate base of [Zn(H₂O)₄]^2⊕ is __________.

Answer the following in one sentence :

Why cations are Lewis acids?

Answer the following in brief :

What are acids and bases according to Arrhenius theory?

Answer the following in brief :

What is meant by conjugate acid-base pair?

Label the conjugate acid-base pair in the following reaction:

\[\ce{HCl + H2O ⇌ H3O\overset{\oplus} + Cl\overset{\ominus}{}}\]

Label the conjugate acid-base pair in the following reaction:

\[\ce{CO^2-_3 + H2O ⇌ OH- + HCO^-_3}\]

Answer the following in brief :

Write a reaction in which water acts as a base.

Answer the following in brief :

Ammonia serves as a Lewis base whereas AlCl₃ is Lewis acid. Explain.

Choose the most correct option.

Two solutions have the ratio of their concentrations 0.4 and ratio of their conductivities 0.216. The ratio of their molar conductivities will be ______.