Question

The lowest oxidation state shown by an element in its compound is ?

• A. $-5$
• B. $-3$
• C. $-4$
• D. $-2$

Answer 1

The correct option is C $-4$

The state of an element or ion in a compound with regard to the electrons gained or lost by the element or ion in the reaction that formed the compound, expressed as a positive or negative number indicating the charge of the ion is defined as the oxidation state.

The lowest oxidation state is $-4,$ as for carbon in methane or for chromium in $\left[Cr\right(CO{)}_4{]}^{4-}$