Ask Question
ChemistryChemistry
19 April, 23:28

What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = pKa? Ka = 1.8*10-5 Quantity = mol Submit b What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = 4.00? Ka = 1.8*10-5 Quantity = mol c What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = 5.00? Ka = 1.8*10-5 Quantity = mol

+2
Answers (1)
  1. 20 April, 02:57
    0
    a) We have to add 0.9 mole NaOH to 1.0 L of 1.8 M HC2H3O2

    b) We have to add 0.277 mole NaOH to 1.0 L of 1.8 M HC2H3O2

    c) We have to add 1.16 mole NaOH to 1.0 L of 1.8 M HC2H3O2

    Explanation:

    a) What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = pKa?

    Step 1: Data given

    Volume of HC2H3O2 = 1.0 L

    Molarity of HC2H3O2 = 1.8 M

    Ka = 1.8*10^-5

    ph = pK = - log (1.8*10^-5) = 4.74

    Step 2:

    Use the Henderson-Hasselbalch equation.

    pH = pKa + log (A-/HA)

    4.74 = 4.74 + log (A-/HA)

    0 = log (A-/HA)

    A-/HA = 1

    Consider X = moles of NaOH added (and moles of A - formed)

    Remaining moles of HA = 1.8 - X

    moles of A - = X

    HA = 1.8 - X

    X / (1.8-X) = 1

    X = 0.9

    We have to add 0.9 mole NaOH to 1.0 L of 1.8 M HC2H3O2

    To control we can do the following equation:

    4.74 = 4.74 + log (0.9/0.9) = 4.74

    b) What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = 4.00?

    Step 1: Data given

    Volume of HC2H3O2 = 1.0 L

    Molarity of HC2H3O2 = 1.8 M

    Ka = 1.8*10^-5

    ph = 4

    Step 2:

    Use the Henderson-Hasselbalch equation.

    pH = pKa + log (A-/HA)

    4 = 4.74 + log (A-/HA)

    -0.74 = log (A-/HA)

    A-/HA = 0.182

    Consider X = moles of NaOH added (and moles of A - formed)

    Remaining moles of HA = 1.8 - X

    moles of A - = X

    HA = 1.8 - X

    X / (1.8-X) = 0.182

    X = 0.277

    We have to add 0.277 mole NaOH to 1.0 L of 1.8 M HC2H3O2

    To control we can do the following equation:

    4 = 4.74 + log (0.277/1.523)

    c) What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = 5.00

    Step 1: Data given

    Volume of HC2H3O2 = 1.0 L

    Molarity of HC2H3O2 = 1.8 M

    Ka = 1.8*10^-5

    ph = 5

    Step 2:

    Use the Henderson-Hasselbalch equation.

    pH = pKa + log (A-/HA)

    5 = 4.74 + log (A-/HA)

    0.26 = log (A-/HA)

    A-/HA = 1.82

    Consider X = moles of NaOH added (and moles of A - formed)

    Remaining moles of HA = 1.8 - X

    moles of A - = X

    HA = 1.8 - X

    X / (1.8-X) = 1.82

    X = 1.16

    We have to add 1.16 mole NaOH to 1.0 L of 1.8 M HC2H3O2

    To control we can do the following equation:

    5 = 4.74 + log (1.16/0.64) = 5
Know the Answer?
Not Sure About the Answer?
Get an answer to your question ✅ “What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = pKa? Ka = 1.8*10-5 Quantity = ...” in 📙 Chemistry if there is no answer or all answers are wrong, use a search bar and try to find the answer among similar questions.
Search for Other Answers
You Might be Interested in
Determine the number of neutrons for the given isotopes. helium-3 carbon-14 nitrogen-15 strontium-90 tellurium-123
Answers (1)
What is the empirical formula of a compound that is 56.95% cu, 14.37% s, and 28.68% o?
Answers (1)
Pre-lab questions 1. a concentration gradient affects the direction that solutes diffuse. describe how molecules move with respect to the concentration.
Answers (1)
The farmhand cut of prime rib at farmer browns steak house weight in at 20 ounces of which 6.0 ounces is good old Nebraska beef fat a person on a 2400 calorie per day diet should not consume more than 800 calories from fat if fat contains 9.
Answers (1)
There are three competing factors at play here: 1. The effective nuclear charge 2. The size of the atom and the force of attraction according to Coulomb's law 3.
Answers (1)
New Questions in Chemistry
What is the percent composition of sulfur compound that contains 20.8 g carbon and 54.4 g sulfur?
Answers (1)
Which of the following is an example of heat transfer by conduction? A. The upstairs of a house being warmer than the downstairs B. Burning your finger on a hot match C. The sun warming your skin D. Being warmed by a fire on a cold night
Answers (2)
How much did John save in his 401 (k) in the 2014 tax year?
Answers (1)
Explain why the chemical released from the injured fish may not cause in a wa why the chemical released from the injured fish may not cause in alarm response in other fish species
Answers (1)
hat historical figure was responsible for developing the system for categorizing living things that is still used today? A) Sir Isaac Newton B) Carolus Linnaeus C) Benjamin Franklin D) Galileo
Answers (1)
Home » Chemistry » What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = pKa? Ka = 1.8*10-5 Quantity = mol Submit b What quantity (moles) of NaOH must be added to 1.0 L of 1.
Sign Up Forgot Password?