2
The hardest substance available on earth is
diamond
3
Washing soda is the common name for
sodium carbonate
4
The gas usually filled in the electric bulb is
nitrogen
5
Chemical formula for water is.
h2o
6
Graphite most use in?
pencils
7
Brass gets discoloured in air because of the presence of which of the following gases in air?
Hydrogen sulphide
8
which of the following is a non metal that remains liquid at room temperature?
bromine