Take the following objects : iron nail/sheet, copper wire, aluminium wire, a piece of coal. Rub each object on a fresh surface of sandpaper and observe. Hammer each object with force. (Take care not to hurt yourself.) Record your observations in the following table.
Object Is the surface shining? yes/no Does the shape flatten/break into small pieces on hammering ?
Iron nail
Copper wire
Aluminium wire
Coal piece
The objects in the above activity are made of the elements iron (Fe), copper (Cu), aluminium (Al) and carbon (C) respectively. Fill the following table on the basis of the observations obtained on doing the above two tests on each of the objects.
Elements having a shiny surface
Elements that flatten on hammering
Elements with a dull surface
Elements that break on hammering
Answers
Answer:
Fe,Cu and Al have shunting surface and flattens on hammering but C have dull surface and breaks when hammered
Explanation:
Elements having a shiny surface - Iron nail, copper wire, and aluminum wire.
Elements that flatten on hammering - Iron nail, copper wire, and aluminum wire.
Element with a dull surface - Coal piece.
Element that breaks on hammering - Coal piece.
• Iron, copper and aluminum are lustrous and malleable metals, whereas, coal is a non-lustrous and brittle non-metal.
Lustrous means something that shines; malleable means something that can be beaten into sheets or flattened; and brittle means something that easily breaks on hitting.
• On rubbing an iron nail, copper wire and aluminum wire on a fresh surface of sand paper, their lustre remain as it is. Thus, their surfaces remain shining.
• On hammering, these three objects get flattened, being made of malleable metals.
• On the other hand, on rubbing a coal piece on a fresh surface of sand paper, it still remains non-lustrous and the surface of the coal piece doesn't shine.
• On hammering the piece of coal, it breaks into pieces as it is brittle in nature.