# What is the conjugate acid of "iodide ion", I^-?

Feb 27, 2017

The conjugate acid of ${I}^{-}$ is $H I$.............

#### Explanation:

The conjugate base of any acid is the original acid LESS a proton, i.e. ${H}^{+}$. And the conjugate acid of any base is the original base PLUS a proton. As in all descriptions of chemical reactivity, both $\text{MASS}$ and $\text{CHARGE}$ are conserved.

And thus the conjugate acid of $\text{iodide anion}$ is $\text{hydroiodic acid}$.

For any acid, to find the conjugate base, simply remove a proton, and conserve mass and charge. To find the conjugate acids, simply add a proton, and likewise conserve mass and charge.

What are the conjugate acids of $N {O}_{3}^{-}$, $H S {O}_{4}^{-}$, $S {O}_{4}^{2 -}$, $H P {O}_{4}^{2 -}$, $M n {O}_{4}^{-}$, $C l {O}_{4}^{-}$?