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vladimir1956 [14]
3 years ago
10

What is the pH of 40.0 mL of a solution that is 0.15 M in CN� and 0.29 M in HCN? For HCN, use Ka = 4.9 * 10^-9

Chemistry
1 answer:
artcher [175]3 years ago
4 0
This is a buffer solution because it consists of a weak acid (HCN) and its conjugate base (CN-)
Since it's a buffer solution, the pH is equal to the pKa of the solution, you would use the henderson-hasslebach equation:
pH = pKa - log([acid]/[base])
pH = -log(4.9*10-9) - log(.29/.15)
pH = about 8
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quester [9]

Answer:

The answer to your question is 92.7%

Explanation:

Balanced Chemical reaction

                             3 Zn  + Fe₂(SO₄)₃   ⇒   2Fe   +   3ZnSO₄

Molecular weight

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                           196.2 g of Zinc ------------------ 112 g of Iron

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                            x = (20.4 x 112) / 196.2

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% yield = \frac{10.8}{11.65}  x 100

% yield = 0.927 x 100

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5 0
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