Physical and Chemical changes

Which of the following is a Chemical change?

• Respiration

• Cutting paper

• Water to ice

• Clouds raining

Which of the following does not undergo Sublimation?

• Napthalene

• Ammonium chloride

• Common salt

• Camphor

Mention any two examples which are Reversible?

Many any two Irreversible changes?

Which characteristic of chemical change is observed when candle burns?

• Change in colour

• Production of sound

• Change in odour

• Production of heat and light

Turmeric turns red when kept in soap. It is a chemical change.

• True

• False

Magnesium + Oxygen gives

• Magnesium oxygen

• Oxygen magnide

• Magnesium oxide

• None

Rusting is harmful because

• It damages Iron

• It weakens Iron

• Both of them

When Iron nails are kept in Copper sulphate, colour changes from _______ to _________

• Blue to green

• Green to blue

• Blue to red

• Red to Green

Rusting can be prevented by?

• Painting and Oiling

• Galvanisation

• Plating

• All of the above