What is the oxidation state of S in S2O32−?
A. +3 B. +2 C. –2 D. +4

it'd be +2

Explanation:

Since 3 atoms of oxygen are present, so its combined oxidation number will be3(−2)=−6. Now this ion contains a charge of−2, where the sum of the oxidation number of all atoms in an atom is equal to−2. So the oxidation number of S in S2O2−3 should be +2.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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