Answer: New concentration of [tex]HC_{6}H_{5}O^{2-}_{7}[/tex] is 0.23 M.
Explanation:
The given data is as follows.
Moles of [tex]HC_{6}H_{5}O^{2-}_{7}[/tex] = 0.06 mol
Moles of [tex]H_{2}C_{6}H_{5}O_{7}[/tex] = 0.08 mol
Therefore, moles of [tex]OH^{-}[/tex] added are as follows.
Moles of [tex]OH^{-}[/tex] = [tex]0.125 \times \frac{25}{1000}[/tex]
= 0.003125 mol
Now, new moles of [tex]HC_{6}H_{5}O^{2-}_{7}[/tex] = 0.06 + 0.003125
= 0.063125
Therefore, new concentration of [tex]HC_{6}H_{5}O^{2-}_{7}[/tex] will be calculated as follows.
Concentration = [tex]\frac{0.063125}{0.275}[/tex]
= 0.23 M
Thus, we can conclude that new concentration of [tex]HC_{6}H_{5}O^{2-}_{7}[/tex] is 0.23 M.