The concept of oxidation number (O.N) is very important in under standing redox reaction s it helps to identify the oxidant / reductant in a redox reaction it also helps to (i) find oiut the possible molecular formula of any neutral compound and (ii) to balance redox reaction
A compound contains atoms of three elements A b and c if the oxidation umber of A is + 2 B is +5 and that of C is -2 the possible formula of the compund is

Options

A. 5
B. 3
C. 2
D. 1

Answer

c

Explanation

`MnO_(4)^(-)+5e^(-)rarrMn^(2+)`
since 1 mole of `MnO_(4)^(-)` accept 5 mole of electrons therefore 5 moles of electrons are lost by 1.67 moles of `M^(x+)`
since `M^(x+)` change to `MO_(3)^(-)` by accepting 3 electrons
`therefore` oxidation state of M
x=+5-3=+2