State whether the following statements are true or false. In case a statement is false, write the corrected statement in your notebook.
a) Cutting of log of wood into pieces is a chemical change. (True/False)
b) Formation of manures from leaves is a physical change. (True/False)
c) Iron pipes coated with zinc do not get rusted easily. (True/False)
d) Iron and rust are the same substances. (True/False)
e) Condensation of steam is not a chemical change. (True/False)
(a) False.
Cutting of log of wood into pieces is a physical change because no new substance is formed and only the physical properties like shape, size, etc. change.
(b) False.
Formation of manures from leaves is a chemical change because manure had different composition of leaves.
(c) True.
Iron pipes coated with zinc do not get rusted easily because zinc prevent iron articles from coming in contact with oxygen, or water, or both.
(d) False.
When iron piece is left in the open for some time, it acquires a film of brownish substance called rust. Hence, iron and rust are different substances.
(e) True.
Condensation of steam is a physical change because water changes its state from vapour to solid.