Classify the following as chemical or physical changes:
-
cutting of trees,
-
melting of butter in a pan,
-
rusting of almirah,
-
boiling of water to form steam,
-
passing of electric current, through water and the water breaking down into hydrogen and oxygen gases,
-
dissolving common salt in water,
-
making a fruit salad with raw fruits, and
-
burning of paper and wood
Answer
- Cutting of trees- Physical change
(During cutting of trees no new substance is formed, hence its a physical change)
Cutting of trees
Link for the above image is given below: -
http://www.ehs.ufl.edu/programs/os/chainsaw/chain-saw-safety-2/
- Melting of butter in a pan - Physical change
(It is a physical change because it is a change of state of matter from solid to liquid
This change is temporary and can be reversed)
Melting of butter in a pan
Link of the above image is given below: -
- Rusting of almirah- Chemical Change
(Rusting is a chemical reaction in which iron reacts with oxygen to form a new substance called rust(ferric oxide), hence its a chemical change)
Rusting of Iron
Link; -
https://www.blendspace.com/lessons/nLU7WkXGv2ZhDQ/chemical-reactions
- Boiling of water to form steam - Physical Change
(It is a physical change because it is a change of state of matter from liquid to gas.
This change is temporary and can be reversed)
The process of boiling and evaporation causing water to change its state from liquid to gaseous - Physical change
Link: -
https://courses.lumenlearning.com/cheminter/chapter/boiling-point/
- Passing of electric current, through water and the water breaking down into hydrogen and oxygen gases - Chemical Change
(Passing current in water breaks it into Hydrogen and Oxygen, hence new substances are formed. Therefore, its a chemical change)
Passing of electricity through water to form separate bubbles of hydrogen and oxygen
Link: - (This image was present on brainly.in which is a platform where answers are given to the asked questions - basically it is not a typical e-learning website, so i have given the link, which contains only the image.)
https://hi-static.z-dn.net/files/d02/27801012c6df320fb0b1709257d95189.gif
- Dissolving common salt in water- Physical Change
(It is a physical change because this change can be reversed to get back salt and water
This can be done by heating salt solution and water.
Water will convert into water vapour and we can get salt at the bottom of container)
Dissolving of common salt in water
Link: -
http://www.morewithmusic.org/2010/05/solute-solvent-solution.html
- Making a fruit salad with raw fruits - Physical Change
(It is a physical change because no new substances are formed and this change can be reversed to get back different fruits)
Fruit salad with raw fruits
Link: -
https://www.vectorstock.com/royalty-free-vector/fruit-yogurt-salad-vector-1813998
- Burning of paper and wood - Chemical Change
(It is a chemical change because when we burn paper and wood,new substances are formed like carbon and smoke. This change cannot be reversed)
Burning of wood
Link: -
Burning of paper
Link: -
