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

Which of the following compounds contain S = O as well as S = S bonds?

(A) Sulphuric acid

(B) Thiosulphuric acid

(C) Sulphurous acid

(D) Thiosulphurous acid

a. Explain the trends in the following properties with reference to group 16:

1 Atomic radii and ionic radii

2 Density

3 ionisation enthalpy

4 Electronegativity

b. In the electolysis of AgNO₃ solution 0.7g of Ag is deposited after a certain period of time. Calulate the quantity of electricity required in coulomb. (Molar mass of Ag is 107.9g mol^-1)

What is molecular formula of oleum?

(a) H₂SO₃

(b) H₂SO₄

(c) H₂S₂O₇

(d) H₂S₂O₈

Write the electronic configuration of the following elements:

Sulphur (Z = 16)

What is the action of concentrated sulphuric acid on phosphorous pentachloride

3.795 g of sulphur is dissolved in 100g of CS₂. This solution boils at 319.81 K. What is the molecular formula of sulphur in solution? The boiling point of CS₂ is 319.45 K. (Given that K_b for CS₂ = 2.42 K kg mol^-1 and atomic mass of S = 32)

H₂O is liquid while H₂S is gas at room temperature. Explain.

What is the action of concentrated sulphuric acid on copper

What is the action of concentrated sulphuric acid on potassium chlorate?

What is the action of dioxygen on Iron

What is the action of dioxygen on Carbon disulfide

Write the molecular and structural formulae of Dithionous acid

Write chemical reactions for different steps in the manufacture of sulphuric acid by lead chamber process. Draw the structure of phosphorous pentachloride

Explain the following properties of group 16 elements :
1) Electro negativity
2) Melting and boiling points
3) Metallic character
4) Allotropy

What are oxides?  Write different types of oxides with one example each.

Write structure and molecular formula for the following compounds:
a. Orthophosphoric acid 
b. Sulphurous acid

Write the formula for pentaamminechlorocobalt (III) sulphate. 

Write uses of sulphur.

Write the reaction of conc. H₂SO₄ with sugar. What is the role of H₂SO₄ in this reaction?

Explain anomalous behaviour of oxygen in group 16 with respect to:

1. Atomicity
2. Magnetic property
3. Oxidation state