What is the $\mathrm{pH}$ of $0.01 \mathrm{M}$ glycine solution? For glycine $\mathrm{K}_{\mathrm{a}_{1}}=4.5 imes 10^{-3}$ and $\mathrm{K}_{\mathrm{a}_{2}}=1.7 imes 10^{-10}$ at $298 \mathrm{~K}$

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What is the $\mathrm{pH}$ of $0.01 \mathrm{M}$ glycine solution? For glycine $\mathrm{K}_{\mathrm{a}_{1}}=4.5 	imes 10^{-3}$ and $\mathrm{K}_{\mathrm{a}_{2}}=1.7 	imes 10^{-10}$ at $298 \mathrm{~K}$

Aicharya · Accepted Answer

Here
$\mathrm{K}=\mathrm{K}_{\mathrm{a}_{1}} \times \mathrm{K}_{\mathrm{a}_{2}}=\left(4.5 \times 10^{-3}ight) \times\left(1.7 \times 10^{-10}ight)$
$=7.65 \times 10^{-13}$
$\begin{aligned}\left[\mathrm{H}^{+}ight] &=\sqrt{\mathrm{K} \cdot \mathrm{C}} \\ &=\sqrt{7.65 \times 10^{-13} \times 0.01} \\ &=\sqrt{7.65 \times 10^{-15}} \\ &=0.87 \times 10^{-7} \mathrm{~mol} / \mathrm{L} \\ \mathrm{pH} &=-\log \left[\mathrm{H}^{+}ight] \\ &=-\log \left[0.87 \times 10^{-7}ight] \\ &=7+0.06=7.06 \end{aligned}$

What is the $\mathrm{pH}$ of $0.01 \mathrm{M}$ glycine solution? For glycine $\mathrm{K}_{\mathrm{a}_{1}}=4…

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