What is the oxidation number for mn in mn2o7? ( provide sign and number)

Answer;

+7

Explanation;

The sum of the oxidation numbers of all of the atoms in a neutral compound is 0. The sum of the oxidation numbers in a polyatomic ion is equal to the charge of the ion. In this case the overall oxidation number is Zero.

Thus; Oxidation number of oxygen is -2

Mn2O7; has 2 manganese atoms and 7 oxygen atoms;

= (2 × y) + ( 7 × -2) = 0

= 2y = 14

y = +7

Oxidation number of Mn in Mn2O7 is +7

the answer to your question is c.

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