Advertisements
Advertisements
प्रश्न
Classify each of the following, as a physical or a chemical change. Give reasons.
(a) Drying of a shirt in the sun.
(b) Rising of hot air over a radiator.
(c) Burning of kerosene in a lantern.
(d) Change the colour of black tea by adding lemon juice to it.
(e) Churning of milk cream to get butter.
Advertisements
उत्तर
Physical changes because there is no change in chemical composition,
(a) Drying of a shirt in the sun.
(b) Rising of hot air over a radiator.
(e) Churning of milk cream to get butter.
Chemical changes because new substances are formed.
(c) Burning of kerosene in a lantern.
(d) Change the colour of black tea by adding lemon juice to it.
APPEARS IN
संबंधित प्रश्न
Fill in the blank:
The basic conditions necessary for a chemical reaction is _______
Write true or false :
When iron and sulphur are heated together a grey mass is formed which is attracted by a magnet .
State what you would observe when the following substance is heated in a glass test tube red lead.
Explain the following reaction with one suitable example of Displacement reaction.
Give an example of the following chemical changes.
A reaction involving
(i) Change of state
(ii) formation of precipitate
Distinguish by heating the following in dry test tubs.
Zinc nitrate and copper nitrate.
Represent the addition of dilute sulphuric acid to zinc by means of a chemical equation. State the function of the arrow between the reactants and products.
Select the correct answer for the following options:
The gas which reacts with oxygen to give a neutral liquid.
NPK are the primary nutrients for plants.
Chemists identify gypsum as a natural indicator.
