HSC Science (General) 12th Standard Board Exam - Maharashtra State Board Question Bank Solutions

How are the following compounds prepared?

benzaldehyde from benzene

Discuss the optical activity of lactic acid.

For a chemical reaction, A→ products, the rate of reaction doubles when the concentration of
‘A’ is increased by a factor of 4, the order of reaction is

(A) 2

(B) 0.5

(C) 4

(D) 1

Which of the following is the first oxidation product of secondary alcohol?

(A) Alkene

(B) Aldehyde

(C) Ketone

(D) Carboxylic acid

Explain the mechanism of alkaline hydrolysis of tert-butyl bromide with energy profile diagram.

Mention the names of various steps involved in the extraction of pure metals from their ores.

The stability order for carbocation is _______.

(A) 2° > 3° > 1° 

(B) 3° > 2° > 1°

(C) 3° > 1° > 2°

(D) 1° > 3° > 2°

How are the following polymers prepared?

Orlon

The temperature at which vapour pressure of a liquid becomes equal to the atmospheric
pressure is _______.

(A) melting point

(B) boiling point

(C) 273 K

(D) 373 K

How is nitromethane prepared from the following?

α-halogen carboxylic acid

Write a note on aldol condensation.

What are thermoplastic polymers?

How are the following compounds prepared?

acetophenone from benzene

How are the following compounds prepared?

benzaldehyde from benzoyl chloride

What is the action of the following reagents on phenol - H₂SO₄ at room temperature.

Write balanced chemical equations for action of ammonia on - acetaldehyde

Write balanced chemical equations for action of ammonia on - acetone

Write balanced chemical equations for action of ammonia on - acetone

The density of iron crystal is 8.54-gram cm^–3. If the edge length of the unit cell is 2.8 A° and atomic mass is 56 gram mol^–1, find the number of atoms in the unit cell.  (Given: Avogadro's number = 6.022x10²³,1A° = 1x10^-8 cm)

Draw the structure of IF₇. Write its geometry and the type of hybridization.