A buffer solution 0.04 M in Na_2HPO_4 and 0.02M in Na_3 PO_4 is prepared. The electrolytic oxidation of 1.0 milli -mole of the organic compound RNHOH is carried out in 100 mLof the buffer. The reaction is RNHOH +H_2O to RNO_2 +4H ^(+) + 4e ^(-) The approximatepH of solution after the oxidation is complete is:[Given : forH_3O PO_4, pK_(a_1)=7.20 , pK_(a_2) =12]

A buffer solution 0.04 M in Na_2HPO_4 and 0.02M in Na_3 PO_4 is prepar

1.	A buffer solution 0.04 M in Na_2HPO_4 and 0.02M in Na_3 PO_4 is prepared. The electrolytic oxidation of 1.0 milli -mole of the organic compound RNHOH is carried out in 100 mLof the buffer. The reaction is RNHOH +H_2O to RNO_2 +4H ^(+) + 4e ^(-) The approximatepH of solution after the oxidation is complete is:[Given : forH_3O PO_4, pK_(a_1)=7.20 , pK_(a_2) =12]
Answer» ` 6.90 ` ` 7.20 ` ` 7. 5` None of these Solution :` {:(PO_4^(3-)+,H^(+)to, HPO_4^(-2)),( 0.02M , 0.04 M , 0.04 M),( -, 0.02 , 0.06M), (- , 0.02M, -):}` ` {:( HPO_4^(-2) ,H^(+) to, H_2PO_4^(-)),( 0.06, 0.02 , 0),( 0.02 , - , 0.02M),( 0.04M, , ):}` ` pH =7.2 +LOG ""(0.04)/(0.02 )=7.5`