Successive dissociation constants of `H_(2)CO_(3)` are `K_(a_(1)) = 10^(-3)` and `K_(a_(2)) = 10^(-6)`. An aqueous solution contains `0.1 MH_(2)CO_(3)` and `0.1 M HCI` at `25^(@)C`
The concentration of `CO_(3)^(2-)` at equilibrium in solution is: (approximately)
A. `10^(-6)M`
B. `10^(-12)M`
C. `10^(-10)M`
D. `10^(-8)M`
