In a chemical change
Burning of candle wick is an example of chemical change as wick gets burnt and new substance is formed with new property.
A substance which is burned to produce heat and light is known as
When water freezes it undergoes a
When water freezes it undergoes a physical change and no new substance is formed.
Which of the following is an example of physical change?
Boiling of water is a physical change as water vapour can be changed into water again by cooling.
What property stays the same during physical and chemical changes?
Plastic industry was started when a chemist made a
Then in 1909, a Belgian chemist named Leo Baekeland created the first entirely synthetic plastic—and it would revolutionize the way many consumer goods were manufactured. Baekeland called his plastic “Bakelite.”
Which of the following is a chemical change?
Rusting of iron is a chemical change as rust is a new substance having new properties unlike the iron.
Crystals of copper sulphate are prepared by the method of
Chemical change are characterised by
Chemical changes are characterised by formation of new substance having new properties
The product formed by dissolving a substance into another is called
The product formed by dissolving a substance into another is called a solution. Solution is a mixture.
Rusting of iron is a slow change but burning of petrol is a
Rusting of iron is slow change as it takes few days on the other hand burning of petrol is a fast change as it takes less than a second.
Ripening of fruit is a
Ripening of fruit is a slow change as it takes time. Ripening of fruit is also desirable as we want to do show.
During chemical changes, ________________ change may not take place.
During chemical changes, change in colour, heat or temperature may takes place but not always the size and shape.
Electric wires or telephone wire became tight during winter and sag a little during summers because metal
Metal wires expand on heating and contract on cooling. The electric wires become tight during winter due to expansion and tight during winter due to contraction.
The process of converting gas into liquid is called
The process of converting gas into liquid is called condensation. Condensation is a physical change.
The chemical name of Baking soda is
The chemical name of Baking soda is Sodium hydrogen carbonates, which is basic in nature.
Air is a
Air is a mixture of gases like nitrogen, oxygen and carbon dioxide along with other gases and other particles.
Tearing of paper in small pieces is an example of
Tearing of paper in small piece is an example of physical change as no new substance is formed and properties remain same.
Magnesium ribbon burns with
Magnesium ribbon burns with brilliant white light to produce magnesium oxide.
Which of the following is a physical change?
Melting of wax is physical change.
In melting of wax, only the state of wax changes from solid to liquid.
It is a reversible reaction and no new substance is formed.
Burning of candle is both physical and chemical change.
When the candle burns, the wax slowly melts which freezes after some time (Physical change).
Burning of wick is a chemical change as it involves combustion.