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
Misha Larkins [42]
3 years ago
13

Starting with 0.250L of a buffer solution containing 0.250 M benzoic acid (C 6H 5COOH) and 0.20 M sodium benzoate (C 6H 5COONa),

what will the pH of the solution be after the addition of 25.0 mL of 0.100M HCl? (K a (C 6H 5COOH) = 6.5 x 10 -5)
Chemistry
1 answer:
Zigmanuir [339]3 years ago
5 0

Answer:

pH = 4.05

Explanation:

The pH of the benzoic buffer can be determined using H-H equation:

pH = pKa + log [A⁻] / [HA]

<em>Where pKa is -logKa = 4.187</em>

pH = 4.187 + log [Sodium Benzoate] / [Benzoic Acid]

<em>Where [] can be understood as moles of each specie.</em>

Thus, to find pH of the buffer we need to calculate moles of benzoic acid and sodium benzoate.

<em>Initial moles:</em>

<em />

Initial moles of benzoic acid and sodium benzoate are:

Acid: 250mL = 0.250L ₓ (0.250 moles / L) = <em>0.0625 moles of benzoic acid</em>

Benzoate : 250mL = 0.20L ₓ (0.250 moles / L) = <em>0.050 moles of sodium benzoate</em>

<em>Moles after reaction:</em>

Now, 0.0250L×(0.100mol/L) = 0.0025 moles of HCl are added to the buffer reacting with sodium benzoate, C₆H₅COONa, producing more benzoic acid, as follows:

HCl + C₆H₅COONa → C₆H₅COOH + NaCl

That means after reaction moles of both species are:

Benzoic acid: 0.0625 mol + 0.0025mol (Moles produced) = 0.065 moles

Sodium Benzoate: 0.050mol - 0.0025mol (Moles that react) = 0.0475 moles

Replacing in H-H equation:

pH = 4.187 + log [0.0475] / [0.065]

pH = 4.05

You might be interested in
What electron transition represents a gain of energy?
leva [86]

Answer:

between the 2 and the 3 shell

Explanation:

when a gain of energy is the displacement of the electrons in a layer of low-energy shell high-energy, and here we have the 2nd shell is the shell of low energy, and 3 shell the shell is high-energy.

4 0
3 years ago
In the picture below, ammonia and bleach are mixed together. How many nitrogen (N) atoms will be in the products?
klasskru [66]

1

ammonia: NH3 (one nitrogen)

bleach: NaOCl (zero nitrogen)

4 0
3 years ago
Two identical pots, one black and one silver, containing exactly the same amounts of water, are heated to the same temperature.
I am Lyosha [343]
The most probable answer is: (a) <span>The black pot emits heat at a faster rate than the silver pot. It means the black pot conducts heat at a higher rate than the silver pot, that's why it cooled off faster. It also means that the silver pot retains heat better and is more of an insulator.</span>
7 0
3 years ago
Read 2 more answers
Define motion of particles in matter
Wittaler [7]

Answer:

Explanation:

The states that all of the particles that make up matter are constantly in motion. As a result, all particles in matter have kinetic energy. The kinetic theory of matter helps explain the different states of matter—solid, liquid, and gas. ... Particles do not always move at the same speed.

5 0
3 years ago
Question 55 pm
Law Incorporation [45]

Answer:

They are magnetic lines and theses lines depict the invisible magnetic field around the magnet! Hope this helps I got it right on my quiz:)

Explanation:

3 0
3 years ago
Other questions:
  • I give 10 points for 3 tasks + BRAINLIEST!!!!
    13·1 answer
  • A solution is prepared by mixing equal volumes of 0.16 M HCl and 0.52 M HNO3. (Assume that volumes are additive.)
    15·1 answer
  • A reaction that occurs when the reactants are simply put together is
    8·1 answer
  • How many sig figs are in<br> 0.006 <br> 0.0605<br> 60.5<br> 605.5<br> 960 x 10^-3<br> 6 <br> 60
    6·1 answer
  • What is the weight, on earth, if a book with a mass of 1.5kg 1.5N 6.5 N 11.3 N 14.7
    10·2 answers
  • What are some things you can do to keep ure heart healthy
    6·2 answers
  • How did the development of the earliest idea about atoms differ from the later work of scientists?
    15·2 answers
  • In the image of the billiard table below, a cue ball is about to be struck and pushed toward the other balls
    6·1 answer
  • CH3CHClCH(CH3)CH2CH2CH2CH2Br name the molecule iupac rules please
    10·1 answer
  • 1. Most of an atom is empty space, except for a tiny, dense core called the ___.
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!