(a). `H_(2)S` is hydrogen sulphide. It is made up of two hydrogen atoms and one sulphur atom. Each hydrogen atom has 1 valence electron whereas a sulphur atom has 6 valence electrons. The sulphur atom shares its two electrons with two hydrogen atoms to form hydrogen sulphide as shown below:
(b). `F_(2)` is fluorine molecule. each fluorine atom has 7 valence electrons. two fluorine atoms share 1 electron each to form a fluorine molecule as shown below.
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