Non-metals are elements that react by gaining electrons to attain a stable configuration and form an anion.
Non-metal elements are found in groups, 5, 6, 7 and 8 of the periodic table. Halogens are an example of non-metals that gain an electron to form anions.
SO₂ is a compound whose molecule contains sulfur and oxygen which are non-metals. The sulfur and oxygen atoms are joined together by a covalent bond to form SO₂.
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