Burning of Magnesium ribbon is a ________ change.
Physical
Chemical
Reversible
Temporary
The formation of rust on the surface of iron is called __________ of iron.
rusting
melting
condensation
none of these
The cells used in a wrist watch undergo:
Physical change
Periodic change
Chemical change
None of these
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
When liquids are heated, they turn into gases. The yellow egg yolk present inside the egg is a liquid but when it is heated, it changes into an omelet which is solid, why?
Sometimes, liquids turn into solids
Omelet does not follow the above rule
Strictly speaking, the rule does not apply to complex mixtures and egg yolk is a complex mixture
The given statement is false
Chemical changes are
temporary
partial
permanent
___________ is known as blue Vitriol.
Copper sulphate
Ferrous sulphate
Sulphuric acid
Zinc oxide
Melting of ice is an example of:
Exothermic reaction
Endothermic reaction
Chemical combination
Chemical decomposition
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
