A chemical change is also known as
Physical reaction
Nuclear reaction
Chemical reaction
None of these
What is the formula of rust ?
Fe3O4
Fe2O3
FeO
none of these
Which of the following is a chemical change ?
Burning of paper
Germination of seed
Formation of coal from the wood
All of these
Which of the following is a chemical change?
Painting wood
Burning paper
Sugar dissolving in water
Iron turning red when heated
Expansion is shown by
a piece of paper
a piece of iron
a piece of cotton
all of the above
Halite is a mineral formed by the evaporation of a solution. Which type of process is evaporation?
Physical
Chemical
Irreversible change
Anaerobic bacteria digest animal waste and produce biogas(Change-A). The biogas is then burnt as fuel (Change-B). The following statements pertain to these changes. Choose the correct one.
Process- A is a chemical change
Process- B is a chemical change
Both process- A and B are chemical changes
None of these process is a chemical change
Which of the following is a physical change ?
Melting of ice
Melting of wax
Formation of steam from water
Sublimation of iodine is an example of ______ change .
physical
chemical
exothermic
When a candle burns,
Physical change occurs
Chemical change occurs
Both the changes occur
None of these changes occur
