ICSE ICSE Class 8 - CISCE Question Bank Solutions

Differentiate between:

A balanced and an unbalanced chemical equation.

Balance the following equation:

N₂ + H₂ → NH₃

Balance the following equation:

H₂ + O₂ → H₂O

Balance the following equation:

Na₂O + H₂O → NaOH

Balance the following equation:

CO + O₂ → CO₂

Balance the following equation:

Zn + HCI →  ZnCI₂ + H₂

Write a balanced chemical equation for the following word equation:

Iron + Chlorine → Iron (III) chloride

Write balanced chemical equations for the following word equation:

Magnesium + dil sulphuric acid → Magnesium sulphate + water

Write balanced chemical equations for the following word equation:

Magnesium + oxygen → Magnesium oxide

Write balanced chemical equations for the following word equation:

Calcium oxide + water → Calcium hydroxide

Write balanced chemical equations for the following word equation:

Sodium + chlorine → Sodium chloride

What information do you get from the following chemical equation:
Zn(s) + 2HCl (dil) → ZnCl₂ (aq) + H₂(g)

Define chemical reaction.

State four conditions necessary for a chemical reaction to take place.

Write balanced chemical equations for the reactions represented by word equations in the conditions for a chemical reaction.

Balance the following equation:

`Fe +O_2    →   Fe_3 O_4`

Balance the following equation:

`Fe+ H_2O   →   Fe_3 O_4+H_2`

Balance the following equation:

`N_2+O_2    →    NO`

Balance the following equation:

`Pb_3 O_4     →    PbO+O_2`

Balance the following equation. Also name the products formed.

`NaNO_3→ NaNO_2  +  O_2 `       Name of product (s)