Calculate the pH of a buffer when the reduction potential of hydrogen electrode placed in the buffer solution is found to be -0.413V .

Question

Calculate the pH of a buffer when the reduction potential of hydrogen electrode placed in the buffer solution is found to be -0.413V . (A) 10 (B) 4 (C) 7 (D) 12

Tardigrade Admin · Accepted Answer

Apply Nernst Equation on the given reduction reaction of hydrogen.

H^{+} (a q) + e^{-} \to \frac{1}{2} H_{2} (g)

E_{ce ll} = E_{ce ll}^{^{\circ}} - \frac{0.059}{n} l o g \frac{1}{[ H ^{+} ]}

Where

E_{H^{+} / H_{2}}^{^{\circ}} = 0 V

and

n = 1

- 0.413 = - 0.059 l o g \frac{1}{[ H ^{+} ]}

or

\frac{0.414}{0.059} = - l o g [H^{+}] = p H

p H = 7

Q. Calculate the $p H$ of a buffer when the reduction potential of hydrogen electrode placed in the buffer solution is found to be $- 0.413 V$ .

$10$

$4$

$7$

$12$

Q. Calculate the pH of a buffer when the reduction potential of hydrogen electrode placed in the buffer solution is found to be −0.413V .

10

4

7

12

Apply Nernst Equation on the given reduction reaction of hydrogen. H+(aq)+e−→21​H2​(g) Ecell​=Ecell∘​−n0.059​log[H+]1​ Where EH+/H2​∘​=0V and n=1 −0.413=−0.059log[H+]1​ or 0.0590.414​=−log[H+]=pH pH=7

Q. Calculate the $p H$ of a buffer when the reduction potential of hydrogen electrode placed in the buffer solution is found to be $- 0.413 V$ .

$10$

$4$

$7$

$12$