Photosynthesis is a _________ change.
Physical
Reversible
Temporary
Chemical
Burning of Magnesium ribbon is a ________ change.
__________ turns lime water milky.
Oxygen
Carbondioxide
Hydrogen
Carbonmonoxide
Cooking of rice is an example of:
Irreversible change
Endothermic reaction
Both A and B
None of these
Rusting of iron is a chemical change because:
It is temporary
It can be cleaned and the original substance recovered
It is a slow reaction
A new substance is formed
The chemical name of baking soda is
Sodium carbonate
Sodium hydrogen carbonate
Calcium phosphate
Calcium oxychloride
The process of depositing a layer of zinc on iron is called
Galvanization
Vulcanization
Polymerization
Condensation
A chemical reaction in which energy is liberated is called:
Exothermic reaction
Physical change
Photo chemical reaction
When nitrogen reacts with hydrogen under high temperature and pressure ammonia, which is also a gas is formed. This is an example of:
Chemical combination
Chemical decomposition
The cells used in a wrist watch undergo:
Periodic change
Chemical change
