Question

what is the oxidation number of As in H2AsO4 briefly explain how does it come??✨

Answer 1

oxidation no shuld be +3 i think

Answer 2

Answer: The oxidation state of arsenic in the given compound is +5.

Explanation:

We are given:

A chemical ion having formula $H_2AsO_4^-$

Oxidation state is defined as the number which is assigned to the element when it gains or loose electrons.

If the element gains electron, it will attain a negative oxidation state and if the element looses electrons, it will attain a positive oxidation state.

We take the oxidation state of arsenic atom be 'x'.

Oxidation state of hydrogen atom = +1

Oxidation state of oxygen atom = -2

Overall charge on the ion = -1

Evaluating the oxidation state of chlorine atom:

$2(+1)+x+4(-2)=-1\\\\x=+5$

Hence, the oxidation state of arsenic in the given compound is +5.