Assertion : Solution of `Na_(2) CrO_(4)` in water is intensely electrons.
Reason : Oxidation state of `Cr` in `Na_(2) CrO_(4)` is `+ VI`.

Options

A. If the both assertion and reason are true and the reason is the correct explanation of the assertion
B. If both assertion and reason are true and the reason is not the correct explanation of the assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false statements.

Answer

A

Explanation

`Na_2CrO_4` solution in water is yellow in colour, when acified changes to organe colour (due to the formation of `Cr_2O_7^(2-)` ions).
`Na_2CrO_4 + H_2SO_4 to Na_2Cr_2O_7+Na_2SO_4+H_2O`
Oxidation state : `Na_2CrO_4`
Let oxidation state of Cr be x
`rArr 2(+1) + x + 4(-2) = 0 rArr x=+6`