What is the colour and formula of Sodium Sulphate?

• Colourless Na2SO4

• White Na2SO4

• Colourless NaSO4

• White Na(SO4)2

In the balanced equation: a. Fe₂O₃ + b. H₂ → c. Fe + d. H₂O

The value of a, b, c, d are respectively –
(A) 1, 1, 2, 3
(B) 1, 1, 1, 1
(C) 1, 3, 2, 3
(D) 1, 2, 2, 3 ?

• A
• D
• B
• C

A balanced chemical equation always obeys

• Law of conservation of mass

• Law of thermal equilibrium

• Law of conservation of energy

• All of the above

During respiration, glucose and oxygen combine in the cells of our body when energy is released. What is the best way to describe the reaction that takes place during the process of respiration?

• Oxidation

• Endothermic

• Exothermic

• Displacement

Which of the following is a thermal decomposition reaction?

• 2H2O → 2H2 + O2

• 2AgCl → 2Ag + Cl2

• H2(g) + Cl2(g) → 2HCl(g)

• ZnCO3 → ZnO + CO2

Single displacement reaction involves ....... reaction .

• Oxidation

• Reduction

• Redox

• Heating

What becomes the colour of iron nails after they have been kept in the blue solution of copper sulfate for about 20 minutes?

• White

• Reddish-brown

• Green

• Blue

A red-brown gas is released on heating lead nitrate. It is an example of

• Combination reaction

• Oxidation reaction

• Decomposition reaction

• Reduction reaction

Barium chloride and sodium sulphate react to produce –

• BaSO4 & NaCl

• Ba2SO4 & NaCl

• BaSO4 & Na2Cl

• None of these.

The action of water on quick lime is an example of which type of reaction ?

• Combination

• Displacement

• Decomposition

• Redox