1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
ELEN [110]
3 years ago
13

What is the Ka of a 0.0326 M solution of hydrofluoric acid with a pH of 3.94?

Chemistry
1 answer:
LenKa [72]3 years ago
8 0

Answer:

Kₐ = 4.06 × 10⁻⁷

Explanation:

Step 1. <em>Calculate [H₃O⁺] </em>

\text{H}_{3}\text{O}^{+} = 10^{\text{-pH}}\text{ mol/L}

pH = 3.94

\text{H}_{3}\text{O}^{+} = 10^{-3.94}} \text{ mol/L}

[H₃O⁺] = 1.15 × 10⁻⁴ mol·L⁻¹

Calculate K_{\text{a}}

                             HF + H₂O ⇌          H₃O⁺          +          F⁻

I/mol·L⁻¹:           0.0326                          0                         0

C/mol·L⁻¹: 0.0326-1.15 × 10⁻⁴        +1.15 × 10⁻⁴           +1.15 × 10⁻⁴

E/mol·L⁻¹:         0.0325                    1.15 × 10⁻⁴            1.15 × 10⁻⁴

So, at equilibrium,

[H₃O⁺] = [F⁻] = 1.15 × 10⁻⁴ mol·L⁻¹

[HF] = 0.326 – 1.15 × 10⁻⁴  mol·L⁻¹ = 0.0325 mol·L⁻¹

Kₐ = {[H₃O⁺][F⁻]}/[HF]

Kₐ = (1.15 × 10⁻⁴ × 1.15 × 10⁻⁴)/0.0325

Kₐ = 1.32 × 10⁻⁸/0.0325

Kₐ = 4.06 × 10⁻⁷

This is <em>NOT</em> a solution of HF (Kₐ = 7.2 × 10⁻⁴). It is more likely a solution of carbonic acid (H₂CO₃; Kₐ₁ = 4.27 × 10⁻⁷).

You might be interested in
Calcium and bromine have formed a bond. Leading up to this, calcium gave up electrons. It was a(n)
scZoUnD [109]
Leading up to this, calcium gave up 2 valence electrons and thus was denoted as a cation. These 2 electrons were transferred to bromine, which received an overall negative charge because of the addition of 2 valence electrons in its valence shell, and thus formed a negatively charged ion, an anion.

Both formed an ionic bond, due to the electrostatic charge of attraction between the 2 oppositely charged ions. If many ions of Ca and Br are present and numerous ionic bonds have formed it will undergo an arrangement which is that of an ionic lattice, type of structure.
6 0
3 years ago
Calculate the boiling temperature of a 0.50 M solution of sucrose. Assume that the concentration is 0.50 m.
Ronch [10]
There is one missing point in the question.

The formula to find an increase in boiling Temperature is :

ΔT = kb x M

ΔT = is the increase in boiling Temperature
Kb = Boiling point constant of the Solvent
M = Molarity

You did not provide the Kb. If you have it, you just have to insert it to the formula to find the ΔT.


And assuming that the other solution is water, you just have to add it up with 100 Celcius


5 0
3 years ago
In a process called photosynthesis, plants use carbon dioxide and water, along with energy from sunlight, to produce sugar and o
Alex Ar [27]

24 molecules of H2O are needed by the plant to produce 4 molecules of sugar.

<h2>What is photosynthesis?</h2>

The process by which plants convert carbon dioxide, water, and sunlight into oxygen and sugar-based energy is known as photosynthesis.

<h3>The photosynthesis equation is as follows:</h3>

                   6CO2 + 6H2O + Sunlight → C6H12O6 + 6O2

The following three significant activities are involved in photosynthesis:

1. Chlorophyll absorbs light energy.

2. Water molecules are divided into hydrogen and oxygen and light energy is converted to chemical energy.

3. Carbon dioxide is converted to sugars.

         

Therefore, a plant needs four molecules of H2O and four molecules of CO2 to make one molecule of glucose or sugar, hence a plant needs 24 molecules of H2O and 24 molecules of CO2 to make four molecules of sugar.

Learn more about photosynthesis here:

brainly.com/question/19160081

#SPJ4

4 0
1 year ago
Why wouldn't the concorde travel lower
Alika [10]

Supersonic flight over land is typically forbidden to minimize disruption to people on the ground. This meant that until it was over open water, Concorde could not operate at its maximum Mach 2 capability.

<h3>What is Concorde?</h3>
  • The Concorde is a tailless aircraft with a drooping nose, an oval delta wing, and a narrow fuselage that allows for seating for 92 to 128 passengers.
  • It's improbable that Concorde will ever fly for an airline again in a commercial capacity. The economics of reactivating Concorde and incorporating it into the fleet of a contemporary airline would be challenging to justify, even if the technical and regulatory concerns could be handled.
  • Supersonic flight over land is usually not allowed to minimize the impact on people on the ground. This meant that Concorde could not operate at its maximum Mach 2 speed until it was over an open body of water.

To learn more about Concorde refer to:

brainly.com/question/14354579

#SPJ1

5 0
1 year ago
Help Ill give you the brainiest answer thing please just give me the right answer
yaroslaw [1]

Answer:

the 3rd one

Explanation:

5 0
3 years ago
Read 2 more answers
Other questions:
  • The dimensions of a cuboid shape cupboard are 1.31 m wide by 0.9 m long by 1.70 m tall what is the volume of the cupboard taking
    11·1 answer
  • Which best describes how isotopes of the same element differ?
    13·1 answer
  • A shallow river dries up is an example of
    10·1 answer
  • Answer question 13. What is the mechanical advantage of a lever that can lift a 100 N load with a input force of 20 N
    5·1 answer
  • The second reaction in the formation of sulfuric acid occurs slowly.
    15·1 answer
  • How many atoms are there in 7.2 mol neon?
    12·1 answer
  • If you start a chemical reaction with 5 atoms of hydrogen, how many hydrogen atoms will you have when it is finished? Group of a
    8·1 answer
  • Define the concentration measurements of parts per million
    5·1 answer
  • What happens to the temperature of a liquid as it is cooled beyond its freezing point?
    8·1 answer
  • when glycerol reacts with three different fatty acids, how many stereogenic centers does the product triacylglycerol contain?
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!