Chapter 10: Q30 P (page 232)

Calculate $α_{H_{2} A}, α_{H A^{-}}, α_{A^{2 -}}$ for cis-butenedioic acid at pH 1.00, 1.92, 6.00, 6.27 and 10.00.

Short Answer

Expert verified

$α_{H_{2} A}, α_{{HA}^{-}}, α_{A^{2 -}}$ for cis-butenedioic acid at pH 1.00, 1.92, 6.00, 6.27 and 10.00 are;

For $H_{2} A$ ;

a. at $p H = 1.00 α (H_{2} A) = 0.893$

b. at $p H = 1.92 α (H_{2} A) = 0.500$

c. at $p H = 6.00 α (H_{2} A) = 5.41 \times 10^{- 5}$

d. at $p H = 6.27 α (H_{2} A) = 2.23 \times 10^{- 5}$

e. at $p H = 10.00 α (H_{2} A) = 1.55 \times 10^{- 12}$

For $H A^{-}$ ;

at $p H = 1.00 α (H A^{-}) = 0.107$

b. at $p H = 1.92 α (H A^{-}) = 0.500$

c. at $p H = 6.00 α (H A^{-}) = 0.651$

d. at $p H = 6.27 α (H A^{-}) = 0.500$

e. at $p H = 10.00 α (H A^{-}) = 1.86 \times 10^{- 4}$

For $A^{2 -}$ ;

a. at role="math" localid="1663566032872" $p H = 1.00 α (A^{2 -}) = 5.76 \times 10^{- 7}$

b. at role="math" localid="1663566040892" $p H = 1.92 α (A^{2 -}) = 2.23 \times 10^{- 5}$

c. at role="math" localid="1663566047030" $p H = 6.00 α (A^{2 -}) = 0.349$

d. at role="math" localid="1663566055571" $p H = 6.27 α (A^{2 -}) = 0.500$

e. at $p H = 10.00 α (A^{2 -}) = 0.999$

Step by step solution

Step 1; Cis-butenedioic acid

A dicarboxylic acid or molecule with 2 carboxyl groups, maleic acid or cis-butenedioic acid would be an organic compound. HO₂CCH=CHCO₂H is its chemical formula. Butenedioic acid comes in two different isomers: fumaric acid and maleic acid.

Step 2; Calculating αH2A,αHA-,αA2- for cis-butenedioic acid;

We will use the following:

$K_{1, 2 . .} = 10^{- {pK}_{a 1, 2 . . .}} {pK}_{a 1} = 1.92 \to K_{1} = 10^{- 1.92}, {pK}_{a 2} = 6.27 \to K_{2} = 10^{- 6.27} pH \to [H^{+}] = 10^{- pH}$

The fraction of $H_{2} A$ would be;

$α (H_{2} A) = \frac{[H^{+}]}{[H^{+}]^{2} + [H^{+}] K_{1} + K_{1} K_{2}}$

So the following would be

a. at $p H = 1.00 α (H_{2} A) = 0.893$

b. at $p H = 1.92 α (H_{2} A) = 0.500$

c. at $p H = 6.00 α (H_{2} A) = 5.41 \times 10^{- 5}$

d. at $p H = 6.27 α (H_{2} A) = 2.23 \times 10^{- 5}$

e. at $p H = 10.00 α (H_{2} A) = 1.55 \times 10^{- 12}$

The fraction of localid="1663566871260" $A^{-}$ would be;

localid="1663566946766" $α (H A^{-}) = \frac{K_{1} [H^{+}]}{[H^{+}]^{2} + [H^{+}] K_{1} + K_{1} K_{2}}$

a. at $p H = 1.00 α (H A^{-}) = 0.107$

b. at $p H = 1.92 α (H A^{-}) = 0.500$

c. at $p H = 6.00 α (H A^{-}) = 0.651$

d. at $p H = 6.27 α (H A^{-}) = 0.500$

e. at $p H = 10.00 α (H A^{-}) = 1.86 \times 10^{- 4}$

The fraction of $A^{2 -}$ would be;

$α (A^{2 -}) = \frac{K_{1} K_{2}}{[H^{+}]^{2} + [H^{+}] K_{1} + K_{1} K_{2}}$

So the following would be;

a. at $p H = 10.00 α (A^{2 -}) = 5.76 \times 10^{- 7}$

b. at $p H = 1.92 α (A^{2 -}) = 2.23 \times 10^{- 5}$

c. at $p H = 6.00 α (A^{2 -}) = 0.349$

d. at $p H = 6.27 α (A^{2 -}) = 0.500$

e. at $p H = 10.00 α (A^{2 -}) = 0.999$

The final answer is;

$α_{H_{2} A}, α_{H A^{-}}, α_{A^{2 -}}$ for cis-butenedioic acid at pH 1.00, 1.92, 6.00, 6.27 and 10.00 are;

For $H_{2} A$ ;

a. at $p H = 1.00 α (H_{2} A) = 0.893$

b. at $p H = 1.92 α (H_{2} A) = 0.500$

c. at $p H = 6.00 α (H_{2} A) = 5.41 \times 10^{- 5}$

d. at $p H = 6.27 α (H_{2} A) = 2.23 \times 10^{- 5}$

e. at $p H = 10.00 α (H_{2} A) = 1.55 \times 10^{- 12}$

For $H A^{-}$ ;

a. at $p H = 1.00 α (H A^{-}) = 0.107$

b. at $p H = 1.92 α (H A^{-}) = 0.500$

c. at $p H = 6.00 α (H A^{-}) = 0.651$

d. at $p H = 6.27 α (H A^{-}) = 0.500$

e. at $p H = 10.00 α (H A^{-}) = 1.86 \times 10^{- 4}$

For $A^{2 -}$ ;

a. at

b. at localid="1663567822632">pH=1.92α(A2-)=2.23×10-5

c. at $p H = 6.00 α (A^{2 -}) = 0.349$

d. at $p H = 6.27 α (A^{2 -}) = 0.500$

e. at $p H = 10.00 α (A^{2 -}) = 0.999$

Unlock Step-by-Step Solutions & Ace Your Exams!

Full Textbook Solutions
Get detailed explanations and key concepts
Unlimited Al creation
Al flashcards, explanations, exams and more...
Ads-free access
To over 500 millions flashcards
Money-back guarantee
We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

Recommended explanations on Chemistry Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Calculate $α_{H_{2} A}, α_{H A^{-}}, α_{A^{2 -}}$ for cis-butenedioic acid at pH 1.00, 1.92, 6.00, 6.27 and 10.00.

Short Answer

Step by step solution

Step 1; Cis-butenedioic acid

Step 2; Calculating αH2A,αHA-,αA2- for cis-butenedioic acid;

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Chemistry Textbooks

The Earths Atmosphere

Chemical Analysis

Chemistry Branches

Organic Chemistry

Making Measurements

Ionic and Molecular Compounds

Study anywhere. Anytime. Across all devices.

Calculate αH2A,αHA-,αA2- for cis-butenedioic acid at pH 1.00, 1.92, 6.00, 6.27 and 10.00.

Short Answer

Step by step solution

Step 1; Cis-butenedioic acid

Step 2; Calculating αH2A,αHA-,αA2- for cis-butenedioic acid;

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Chemistry Textbooks

The Earths Atmosphere

Chemical Analysis

Chemistry Branches

Organic Chemistry

Making Measurements

Ionic and Molecular Compounds

Study anywhere. Anytime. Across all devices.

Calculate $α_{H_{2} A}, α_{H A^{-}}, α_{A^{2 -}}$ for cis-butenedioic acid at pH 1.00, 1.92, 6.00, 6.27 and 10.00.