Question

1. Differentiate between reversible and irreversible changes.
2. Differentiate between physical and chemical changes.
3. What is the effect of heating and cooling on some materials?
4. Which are the processes involved in conversion of water into various states? Name the
states.

1. Why do water pipes usually crack in winter?
2. A potter gives clay in the shape of pot. He bakes these pots in oven. Can the potter get
back the raw clay?
3. Formation of clouds is usually a physical change. Justify the statement.
4. Why the blacksmith heats the metal rim to fix it on the cartwheel?
5. If you leave a piece of iron outside for a long time it turns brown leading to the formation
of rust. Is the change reversible or irreversible?
6. Why dissolving sugar in water is a reversible and physical change?
7. List any 3 properties of physical change.
8. You need to put a metal rod into a hole in a metal cylinder. It is too tight. Can you suggest
the best strategy to make the rod fit in the cylinder? (IBT – 2016)
9. Shashank blew two balloons : one balloon with his mouth and the other balloon with the
vapours coming out of boiling water.

Answer 1

Bull and is reversible changes the changes which can be reversed again and again such as the melting of ice again for me to all it is known as reversible change reversible change like such as burning of paper once it is one will get asked you it won’t again change it to be but differentiate between physical change and chemical changes the changes what appear to physically an onus is equal change the change the topic chemically are known as a chemical changes examples of Gajan this is melting of ice examples of chemical change is burning of paper what is the effect of heating and cooling on some materials it’s that Bull and is reversible changes the changes which can be reversed again and again such as the melting of ice again formants all it is known as reversible change reversible change like such as burning of paper answer this one w Bull and is reversible changes the changes which can be reversed again and again such as the melting of ice again for me to all it is known as reversible change reversible change like such as burning of paper answer this one will get a Shiva it won’t again change it to be but differentiate between physical change and chemical change the changes that appear to physically an onus is equal change the change the topic chemically are known as a chemical changes examples of Gajan this is melting of ice examples of chemical change is burning of paper what is the effect of heating and cooling on some materials it’s that when heating it does not happen anything but on cooling it appears to be some more different states are solid state gassiest state and liquid state know the body does not get the rock Le back justify the statement it means the water cycle happened over there you just read about water cycle if you does not heated it doesn’t fix it it doesn’t fix into it and do it does not stick to it properly it’s a reversible change it was asked it won’t get back dissolving sugar in water is a physical change the properties of physical change there again reversible taken easily be done