Question

Why doesn’t water produce ${\mathbf{10}}^{\mathbf{-}\mathbf{7}}\mathbf{M}\mathbf{}{\mathbf{H}}^{\mathbf{+}}$, andwhen

is added?

Short answer

HBr is a strong acid; when it is dissolved in water, it gets completely disassociated into ${\mathrm{H}}^{+}$and ${\mathrm{Br}}^{-}$

Step-by-step solution

Define strong acid

A strong acid undergoes complete dissociation in water. For example, HBr is a strong acid that undergoes complete water dissociation.

Explain the concentration of H+ ions

The concentration of ${\mathrm{H}}^{+}$ions released by water can be neglected when HBr is dissolved in it because HBr is a strong acid and undergoes complete dissociation. The concentration of ${\mathrm{H}}^{+}$ is merely due to HBr.

$\mathrm{HBr}\left(\mathrm{aq}\right)\to {\mathrm{H}}^{+}\left(\mathrm{aq}\right)+{\mathrm{Br}}^{-}\left(\mathrm{aq}\right)$