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Phoenix [80]
2 years ago
9

You need to produce a buffer solution that has a pH of 4.97. You already have a solution that contains 10. mmol (millimoles) of

acetic acid. How many millimoles of acetate (the conjugate base of acetic acid) will you need to add to this solution?
Chemistry
1 answer:
motikmotik2 years ago
5 0

Answer:

16.9 mmoles are needed to add to the solution

Explanation:

To solve this, we can apply the Henderson Hasselbach equation:

Acetic acid → CH₃COOH

CH₃COOH  +  H₂O  ⇄  CH₃COO⁻   +  H₃O⁺             Ka

That is the acid base equilibrium, to determine the amount:

pKa of acetic acid is 4.74

Henderson Hasselbach formula is:

pH = pKa + log (base/acid)

We replace  →  4.97 = 4.74 + log (B / 10mmoles)

Let's verify mmoles of B

4.97 - 4.74 = log (B/10)

0.23 =  log (B/10)

10^(0.23) = 10^(log (B/10)

1.698 = B/10

B = 1.698 . 10 → 16.9 mmoles

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if three oxygen particles are needed to form ozone, how many units of ozone could be formed from 6 oxygen particles? from 9? fro
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<h3>Answers:</h3>

             1) 2 Units of Ozone

             2)  3 Units of Ozone

              3)  9 Units of Ozone

<h3>Solution:</h3>

1)  From 6 Oxygen Particles;

As given,

                          3 Oxygen Particles form  =  1 Unit of Ozone

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                      6 Oxygen Particles will form  =  X Units of Ozone

Solving for X,

                      X =  (6 O Particles × 1 Unit of Ozone) ÷ 3 O Particles

                      X =  2 Units of Ozone

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As given,

                           3 Oxygen Particles form  =  1 Unit of Ozone

So,

                      9 Oxygen Particles will form  =  X Units of Ozone

Solving for X,

                      X =  (9 O Particles × 1 Unit of Ozone) ÷ 3 O Particles

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                             3 Oxygen Particles form  =  1 Unit of Ozone

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                      27 Oxygen Particles will form  =  X Units of Ozone

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Answer:

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Explanation:

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Then we can<u> calculate the mass of 0.199 moles of arsenic</u>, using its<em> molar mass</em>:

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Answer:

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Explanation:

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