What is the oxidation number of chlorine in hclo4?

CIO4-=-1

CI=4O=-1

O has a 2- oxidation change so

CI+4(-2)=-1

CI+(-8)=-1

CI=-1+8=7

So the oxidation number of chlorine is 7 in this case

the only liquid elements at standard temperature and pressure are bromine (br) and mercury (hg). although, elements caesium (cs), rubidium (rb), francium (fr) and gallium (ga) become liquid at or just above room temperature.

explanation:

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