(English Medium) ICSE Class 10 - CISCE Question Bank Solutions

Name two colourless gases, which when mixed, produce a white solid.

Solution A reacts with an acid B (which gives greenish yellow gas on reacting with oxidizing agents like Pb₃O₄) to give white precipitate C insoluble in nitric acid but soluble in ammonium hydroxide. Name A, B and C.

How is the following metallic oxide reduced? Write equations:

Iron (ll) oxide

How is the following metallic oxide reduced? Write the equation:

Zinc oxide

Explain with reason: 

In the electrolytic reduction of alumina, the graphite anode is gradually consumed.

Draw electron - dot structure and structural formula of methane.

When sodium chloride is heated with concentrated sulphuric acid below 200°C, one of the products formed is ______.

Write a balanced chemical equation for each of the following reactions :
(i) Reduction of copper (II) oxide by hydrogen

Calculate the number of moles in 12g of oxygen gas.

The covalent bond in which the electrons are shared equally between the combining atoms. 

Taking hydrogen chloride and methane as examples, distinguish between a polar covalent bond and a non polar covalent bond.

Explain the following briefly:
Sodium chloride dissolves in water but carbon tetra chloride is insoluble in water.

Explain the following briefly.
Pure water does not conduct electricity, but on adding sodium chloride to it, it starts conducting electricity.

Explain the following briefly:
Cl₂ is a non polar molecule, while HCl is a polar molecule.

Give examples for the following:
Two solid covalent compounds.

Give examples for the following:
Two liquid non polar compounds.

Give examples for the following:
Two gaseous polar compounds.

Give examples for the following:
Two gaseous non polar compounds.

What do you understand by lone pair and shared pair?