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
Papessa [141]
3 years ago
11

Calculate the concentration of buffer components present in 295.00 mL of a buffer solution that contains 0.390 M NH4Cl and 0.390

M NH3 immediately after the addition of 1.40 mL of 6.00 M HNO3.
Chemistry
1 answer:
aivan3 [116]3 years ago
8 0

Answer:

Explanation:

The acid HNO₃ will react with the base NH₃ in the buffer to produce NH₄⁺, changing the concentrations of both NH₃ and NH₄⁺ in the buffer.

Therefore, this question is solved by performing stoichiometric calculations based on those reactions:

HNO₃       +      NH₃     ⇒        NH₄⁺

Vol HNO₃ = 1.40 mL x 1L / 1000 mL = 1.4 x 10⁻³ L

# mol HNO₃ = 1.4 x 10⁻³ L x 6.00 mol/L =  8.4 x 10⁻³ mol HNO₃

Since the reaction occurs in 1:1 ratio, 8.4 x 10⁻³ mol NH₃ will be consumed and 8.4 x 10⁻³ mol of NH₄⁺ will be produced.

Initially we had

# mol NH₄⁺ = 0.295 L x 0.390 mol/L =  0.115 mol

# mol NH₃ = 0.115

After reaction we will have

# mol NH₄⁺  = 0.115 mol + 8.4 x 10⁻³ mol = 0.123 mol

# mol NH₃ = 0.115 mol - 8.4 x 10⁻³ mol = 0.107 mol

Therefore, their new concentrations will be

Volume after reaction = 0.295 L +0 .0014 L = 0.296 L

[NH₄⁺] = 0.123 mol / 0.296 L = 0.416 M

[NH₃] = 0.107 mol / 0.296 L = 0.361 M

You might be interested in
Which of the following has the best buffering capacity. (Buffering capacity can be thought of as the amount of strong acid or ba
OleMash [197]

Answer:

The buffer d has the best buffering capacity.

Explanation:

It is possible to obtain the pH of a buffer using Henderson-Hasselbalch formula:

pH = pka + log₁₀ [A⁻]/[HA]

For CH₃COOH/CH₃COONa buffer:

pH = 4,8 + log₁₀ [CH₃COONa]/[CH₃COOH]

a. pH of this buffer is:

pH = 4,8 + log₁₀ [0,4]/[0,2]

pH = 5,1

As buffering capacity can be thought of as the amount of strong acid that must be added to a buffered solution to change its pH by 1:

For a pH of 4,1:

4,1 = 4,8 + log₁₀ [0,4-x]/[0,2+x]

Where x are the moles of strong acid added.

0,200 = [0,4-x]/[0,2+x]

0,0400 + 0,2x = 0,4 - x

<em>x = 0,3 mol</em>

d. pH of this buffer is:

pH = 4,8 + log₁₀ [0,4]/[0,6]

pH = 4,62

For a pH of 3,62:

3,62 = 4,8 + log₁₀ [0,4-x]/[0,6+x]

Where x are the moles of strong acid added.

0,066 = [0,4-x]/[0,6+x]

0,0396 + 0,066x = 0,4 - x

<em>x = 0,338 mol</em>

e. pH of this buffer is:

pH = 4,8 + log₁₀ [0,3]/[0,6]

pH = 4,5

For a pH of 3,5:

3,5 = 4,8 + log₁₀ [0,3-x]/[0,6+x]

Where x are the moles of strong acid added.

0,050 = [0,3-x]/[0,6+x]

0,030 + 0,05x = 0,3 - x

<em>x = 0,257 mol</em>

Thus, <em>buffer d needs more strong acid to change its pH. That means that have the best buffering capacity</em>

You can do the same process using strong base (Increasing pH in 1) and you will obtain the same results!

I hope it helps!

7 0
3 years ago
A metal ion (X) with a charge of 4+ is attracted to non metal ion (Z) with a charge of 3-. Which of these formulas represents th
Brums [2.3K]

Answer:

D

Explanation:

the charges need to balence out

so finding the LCM which is 12 we find we need 3x's

and 4 zs

so that makes the formula X3Z4 which is D

6 0
2 years ago
PLEASE HELP BEFORE 7 A.M. PACIFIC TIME <br> SEE ATTACHED.
anastassius [24]
For i: 33mL
For ii: 87-88mL
For iii:22.3mL
5 0
3 years ago
Read 2 more answers
How does electronegativity affects the type of intramolecular bond that is formed between atoms
Effectus [21]

Answer:

If the electronegativity difference between bonded atoms are too much high ionic bonds are formed if the electronegativity diference is 0.4 or less than 0.4 non polar covalnet bond formed the difference greater than 0.4 polar covalent bond formed.

Explanation:

Ionic bond:

It is the bond which is formed by the transfer of electron from one atom to the atom of another element.  

Both bonded atoms have very large electronegativity difference. The atom with large electronegativity value accept the electron from other with smaller value of electronegativity.

For example:

Sodium chloride is ionic compound. The electronegativity of chlorine is 3.16 and for sodium is 0.93. There is large difference is present. That's why electron from sodium is transfer to the chlorine. Sodium becomes positive and chlorine becomes negative ion.

Covalent bond:

It is formed by the sharing of electron pair between bonded atoms.  

The atom with larger electronegativity attract the electron pair more towards it self and becomes partial negative while the other atom becomes partial positive.

For example:

In water the electronegativity of oxygen is 3.44 and hydrogen is 2.2. That's why electron pair attracted more towards oxygen, thus oxygen becomes partial negative and hydrogen becomes partial positive.

5 0
3 years ago
How many Helium atoms are in 12 grams of Helium?
horsena [70]
12gHe/1 × 1molHe/4.0026g × 6.02x10^23atomHe/1mol = 1.8 atoms
6 0
3 years ago
Other questions:
  • Which element's total number of electrons is equal to the number of core
    10·1 answer
  • What does it mean for a weak acid to be in equilibrium?
    5·1 answer
  • The combustion of octane, C8H18, proceeds according to the reaction
    13·2 answers
  • The components of a longitudinal wave include __________.
    5·1 answer
  • 15. Discuss the various factors which affect the rate of evaporation. Latent heat
    9·1 answer
  • A 150 j of energy is added to a system that does 50 j of work is done. By how much wiull the internal energy of the system be ra
    7·2 answers
  • How do sediments become<br> sedimentary rock?
    8·1 answer
  • A soccer player kicks a soccer ball. The ball travels 20 meters before landing on the ground. The ball stayed in the air for 5 s
    15·1 answer
  • All participants in the Genius dog challenge are border collies which some experts think are the what breed of dog?
    6·1 answer
  • What is the mole fraction of a solute in a 2.2 molal solution in which naphthalene (C10H8) is the solvent?
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!