ICSE ICSE Class 7 - CISCE Question Bank Solutions for Chemistry

Complete and balance the following chemical equation.

\[\ce{KClO3 ->[heat]  ??   + O2}\]

Which one of the following is most likely to be corroded?

What happens when the mercuric oxide is heated?

What happens when Phosphorus burns in oxygen? Also, give the balanced chemical equation for the reaction.

Classify Copper oxide. Also give a balanced equation to prepare it.

Classify Sulphur dioxide. Also give a balanced equation to prepare it.

Classify Phosphorus pentoxide. Also give a balanced equation to prepare it.

Classify Magnesium oxide. Also give a balanced equation to prepare it.

Describe your observations when potassium nitrate crystals are heated strongly in a test tube and a glowing splint is held near the mouth of test tube.

How will you prove that oxide formed by sulphur is acidic in nature?

Write fully balanced equation for the following :

P₂O₅    +   H₂O   →

Define a chemical change. Give two examples of the above changes.

Change is the law of nature and occurs in our everyday life, at all times and in all places. Differentiate between the following change with a suitable example.

Desirable and undesirable change.

Change is the law of nature and occurs in our everyday life, at all times and in all places.
Differentiate between the following change with a suitable example.

Periodic and non-periodic change

Change is the law of nature and occurs in our everyday life, at all times and in all places.
Differentiate between the following change with a suitable example.

Slow and fast change.

Change is the law of nature and occurs in our everyday life, at all times and in all places.
Differentiate between the following change with a suitable example.

Natural and man-made change.

Differentiate between a physical change and a chemical change with reference to – Nature of change is temporary and reversible or permanent and irreversible.

Differentiate between a physical change and a chemical change with reference to – Formation of products.

Differentiate between a physical change and a chemical change with reference to – Energy change taking place during the respective change.

Give three reasons why melting of wax, is considered a physical change while burning of a candle, a chemical change.