An element $A$ in a compound ABD has oxidation number ${A^{n - }}$. It is oxidized by ${\rm{C}}{{\rm{r}}_2}{\rm{O}}_7^{2 - }$ in acidic medium. In the experiment $1.68 \times {10^{ - 3}}$ mole of ${{\rm{K}}_2}{\rm{C}}{{\rm{r}}_2}{{\rm{O}}_7}$ were used for $3.26 \times {10^{ - 3}}$ mole of $ABD$. The new oxidation number of $A$ after oxidation is :

NEET UG CHEMISTRY MCQ: REDOX REACTIONS

1 Hard

1 of 1

Application +4 | -1

An element

A

in a compound ABD has oxidation number

{A^{n - }}

. It is oxidized by

\mathrm{C}{\mathrm{r}_2}\mathrm{O}_7^{2 - }

in acidic medium. In the experiment

1.68 \times {10^{ - 3}}

mole of

{\mathrm{K}_2}\mathrm{C}{\mathrm{r}_2}{\mathrm{O}_7}

were used for

3.26 \times {10^{ - 3}}

mole of

ABD

. The new oxidation number of

A

after oxidation is :

View answer and explanation

Correct option: B

3 - n

Option B (

3 - n

) is correct because the oxidation state of A increases by 3 due to the reaction with dichromate, thus the new oxidation number is

n - + 3