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
Paul [167]
3 years ago
12

The value of Ka for nitrous acid (HNO2) at 25 ∘C is 4.5×10−4 .a. Write the chemical equation for the equilibrium that correspond

s to Ka1. H+(aq)+NO−2(aq)⇌HNO2(aq)2. HNO2(aq)⇌H+(aq)+NO−2(aq)3. HNO2(aq)⇌H−(aq)+NO+2(aq)4. HNO2(aq)+H+(aq)⇌H2NO+2(aq)5. HNO2(aq)+H−(aq)⇌H2NO+2(aq)​b. By using the value of Ka , calculate ΔG∘ for the dissociation of nitrous acid in aqueous solution. c. What is the value of ΔG at equilibrium? d. What is the value of ΔG when [H+] = 5.9×10−2 M , [NO−2] = 6.7×10−4 M , and [HNO2] = 0.21 M ?
Chemistry
1 answer:
kvv77 [185]3 years ago
6 0

Answers and Explanation:

a)- The chemical equation for the corresponden equilibrium of Ka1 is:

2. HNO2(aq)⇌H+(aq)+NO−2

Because Ka1 correspond to a dissociation equilibrium. Nitrous acid (HNO₂) losses a proton (H⁺) and gives the monovalent anion NO₂⁻.

b)- The relation between Ka and the free energy change (ΔG) is given by the following equation:

ΔG= ΔGº + RT ln Q

Where T is the temperature (T= 25ºc= 298 K) and R is the gases constant (8.314 J/K.mol)

At the equilibrium: ΔG=0 and Q= Ka. So, we can calculate ΔGº by introducing the value of Ka:

⇒ 0 = ΔGº + RT ln Ka

   ΔGº= - RT ln Ka

   ΔGº= -8.314 J/K.mol x 298 K x ln (4.5 10⁻⁴)

  ΔGº= 19092.8 J/mol

c)- According to the previous demonstation, at equilibrium ΔG= 0.

d)- In a non-equilibrium condition, we have Q which is calculated with the concentrations of products and reactions in a non equilibrium state:

ΔG= ΔGº + RT ln Q

Q= ((H⁺) (NO₂⁻))/(HNO₂)

Q= ( (5.9 10⁻² M) x (6.7 10⁻⁴ M) ) / (0.21 M)

Q= 1.88 10⁻⁴

We know that   ΔGº= 19092.8 J/mol, so:

ΔG= ΔGº + RT ln Q

ΔG= 19092.8 J/mol + (8.314 J/K.mol x 298 K x ln (1.88 10⁻⁴)

ΔG= -2162.4 J/mol

Notice that ΔG<0, so the process is spontaneous in that direction.

You might be interested in
A technician needs 500.0mL of a 0.500 M MgCl2 solution for some lab procedures. The stock bottle is labeled 4.00 M MgCl2. What v
mihalych1998 [28]

Answer:

Explanation:

To solve this problem, we need to obtain the number of moles of the solute we desired to prepare;

    Number of moles  = molarity x volume

Parameters given;

        volume of solution = 500mL  = 0.5L

          molarity of solution = 0.5M

   Number of moles  =  0.5 x 0.5  = 0.25moles

Now to know the volume stock to take;

           Volume of stock = \frac{number of moles }{molarity}

  molarity of stock  = 4M

                 volume  = \frac{0.25}{4}   = 0.0625L or 62.5mL

4 0
3 years ago
Caed for this question.
OLga [1]

Answer:

0.962 atm.

97.4 kPa.

731 torr.

14.1 psi.

97,434.6 Pa.

Explanation:

Hello.

In this case, given the available factors equaling 1 atm of pressure, each required pressure turns out:

- Atmospheres: 1 atm = 760 mmHg:

p=731mmHg*\frac{1atm}{760mmHg} =0.962atm

- Kilopascals:: 101.3 kPa = 760 mmHg:

p=731mmHg*\frac{101.3kPa}{760mmHg} =97.4kPa

- Torrs: 760 torr = 760 mmHg:

p=731mmHg*\frac{760 torr}{760mmHg} =731 torr

- Pounds per square inch: 14.69 psi = 760 mmHg:

p=731mmHg*\frac{14.69}{760mmHg} =14.1psi

- Pascals: 101300 Pa = 760 mmHg:

p=731mmHg*\frac{101300Pa}{760mmHg} \\\\p=97,434.6Pa

Best regards.

5 0
3 years ago
Which compound has the LEAST percent composition by mass of sulfur?
Eddi Din [679]

Answer: srs with 32.38 grams

Explanation:

5 0
3 years ago
73.4 km to m then answer in correct number of significant numbers
Fittoniya [83]

Answer:

<em><u>To determine the number of significant figures in a number use the following 3 rules:</u></em>

<em><u>To determine the number of significant figures in a number use the following 3 rules:Non-zero digits are always significant.</u></em>

<em><u>To determine the number of significant figures in a number use the following 3 rules:Non-zero digits are always significant.Any zeros between two significant digits are significant.</u></em>

<em><u>To determine the number of significant figures in a number use the following 3 rules:Non-zero digits are always significant.Any zeros between two significant digits are significant.A final zero or trailing zeros in the decimal portion ONLY are significant.</u></em>

8 0
2 years ago
Which of the following chemical symbols represents the element silver?
notsponge [240]
Silver is Ag from the latin Argentum

Lead is Pb from the latin Plumbum
8 0
3 years ago
Read 2 more answers
Other questions:
  • In chemistry class, you are given a density column with golden syrup, water, and oil. Your teacher gives you an unknown substanc
    12·2 answers
  • True or false? an element consists of only single atoms of that element. <br> a. True <br> b. False
    9·1 answer
  • If 7.17 g of CuNO3 is dissolved in water to make a 0.470 M solution, what is the volume of the solution?
    11·1 answer
  • 2. Among the complexes K4[Cr(CN)6] (A),K4[Fe(CN)6] (B) , K3[Co(CN)6] (C) , K4[Mn(CN)6] (D), Jahn-Teller distortion is shown by *
    6·1 answer
  • What would be the products for the reaction Br2 + KI →? (Just identify the correct products for the reaction. You do not need to
    6·1 answer
  • Which is a characteristic of nuclear fission
    7·2 answers
  • A 19.13 gram sample of chromium is heated in the presence of excess bromine. A metal bromide is formed with a mass of 77.92 g. D
    5·1 answer
  • Given the equations below, what is the heat of reaction for the process in which carbon monoxide is formed from its elements?
    15·2 answers
  • Help me ples HELP HELP HELP HELP HELP
    9·1 answer
  • Coastal waves dissolving limestone sediments
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!