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
Hunter-Best [27]
3 years ago
14

A buffer solution contains 0.306 M C6H5NH3Br and 0.418 M C6H5NH2 (aniline). Determine the pH change when 0.124 mol HCl is added

to 1.00 L of the buffer.
Chemistry
1 answer:
Ulleksa [173]3 years ago
8 0

<u>Answer:</u> The pH change of the buffer is 0.30

<u>Explanation:</u>

To calculate the pH of basic buffer, we use the equation given by Henderson Hasselbalch:

pOH=pK_b+\log(\frac{[\text{conjugate acid}]}{[\text{base}]})

pOH=pK_b+\log(\frac{[C_6H_5NH_3^+]}{[C_6H_5NH_2]})        .....(1)

We are given:

pK_b = negative logarithm of base dissociation constant of aniline  = 9.13

[C_6H_5NH_3^+]=0.306M

[C_6H_5NH_2]=0.418M

pOH = ?

Putting values in equation 1, we get:

pOH=9.13+\log(\frac{0.306}{0.418})\\\\pOH=8.99

To calculate pH of the solution, we use the equation:

pH+pOH=14\\pH_{initial}=14-8.99=5.01

To calculate the molarity, we use the equation:

\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}

Moles hydrochloric acid solution = 0.124 mol

Volume of solution = 1 L

Putting values in above equation, we get:

\text{Molarity of HCl}=\frac{0.124}{1L}\\\\\text{Molarity of HCl}=0.124M

The chemical reaction for aniline and HCl follows the equation:

                   C_6H_5NH_2+HCl\rightarrow C_6H_5NH_3^++Cl^-

<u>Initial:</u>           0.418        0.124           0.306

<u>Final:</u>             0.294          -                0.430

Calculating the pOH by using using equation 1:

pK_b = negative logarithm of base dissociation constant of aniline  = 9.13

[C_6H_5NH_3^+]=0.430M

[C_6H_5NH_2]=0.294M

pOH = ?

Putting values in equation 1, we get:

pOH=9.13+\log(\frac{0.430}{0.294})\\\\pOH=9.29

To calculate pH of the solution, we use the equation:

pH+pOH=14\\pH_{final}=14-9.29=4.71

Calculating the pH change of the solution:

\Delta pH=pH_{initial}-pH_{final}\\\\\Delta pH=5.01-4.71=0.30

Hence, the pH change of the buffer is 0.30

You might be interested in
A(n) ____ is a well blended mixture that appears to be a single substance
Savatey [412]

Answer:

Solution

Explanation:

Compound - a chemical substance made by elements of different densities to form a chemical union.

Element - Any one of the simple chemical substances that can't decompose in a chemical reaction

8 0
3 years ago
What would you observe in a solution of 30 g of KC1O3 in 100 g of water at 10 c?
Mrac [35]

Answer:

Option A is correct. About 5 g of the KClO3 is dissolved

Explanation:

KClO3 is not very good soluble in water.

So, Option C is impossible, because KClO3 is poorly soluble in water.

The low solubility of KClO3 in water causes KClO3 to isolate itself from the reaction mixture by precipitating out of solution.

So, option D will either happen.There will be a part of KClO3 dissolve.

At 10 °C, KClO3 has a solubility of 4.46 g/100 gram (10 °C).

Option A is correct. About 5 g of the KClO3 is dissolved

7 0
3 years ago
The following solutions are prepared by dissolving the requisite amount of solute in water to obtain the desired concentrations.
lions [1.4K]

Answer:

1M MgCl₂ > 1M KCl > 1M C₁₂H₂₂O₁₁

Explanation:

The osmotic pressure (π) is the pressure needed to impede the osmose, it means that it's the necessary pressure to prevent the solvent to go through a membrane.

It can be calculated by:

π = M*R*T*i

Where M is the molarity of the solution (mol/L), R is the ideal gas constant, T is the temperature, and i the van't Hoff factor.

This factor is a way to correct the number of particles that are dissolved in a solute, and it can be calculated by:

i = 1 + α*(q - 1)

Where α is the degree of dissociation of a substance, and q is the number of moles of each ion released in a solution. Thus, covalent compounds that didn't ionize, such as sugars, have only one particle, and q = 1, and so i =1.

Because all the substances have the same molarity (1 M) and are at the same temperature, let's analyze the value of i, which is directly proportional to π.

C₁₂H₂₂O₁₁ is a sugar that didn't ionize, so π = 1;

Both KCl and MgCl₂ are soluble salts and will dissociate completely (α = 1), but MgCl₂ will have 3 particles (Mg²⁺ + 2Cl⁻), and KCl only one particle (K⁺ and Cl⁻), so qMgCl₂ > 1KCl, and so πMgCl₂ > πKCl, which will be higher than 1.

1M MgCl₂ > 1M KCl > 1M C₁₂H₂₂O₁₁

5 0
3 years ago
What is the type of decay chain involved radon 222?
Black_prince [1.1K]
Its a chemical element with symble
5 0
3 years ago
Difference between rapid combustion and spontaneous combustion.
statuscvo [17]

Answer: The difference between rapid combustion and spontaneous combustion...

Explanation:

Rapid combustion is a form of combustion, otherwise known as a fire, in which large amounts of heat and light energy are released, which often results in a flame.Whereas spontaneous combustion is the ignition of organic matter (e.g. hay or coal) without apparent cause, typically through heat generated internally by rapid oxidation.

6 0
3 years ago
Other questions:
  • Which of these equations is balanced?
    13·2 answers
  • 28Which is true?
    12·1 answer
  • Sodium chloride (NaCl) is the chemical name for table salt and potassium chloride (KCl) is a common salt substitute. Using the p
    11·1 answer
  • Sugar dissolves when stirred into coffee. The coffee is the ________, the sugar is the ________, and the sweetened coffee is the
    10·1 answer
  • How many atoms are in the product of the following reaction?
    12·1 answer
  • Thermal energy naturally flows from _________ matter to _______ matter.
    9·1 answer
  • The element in Group 14 Period 4 has how many neutrons and is it a metal, nonmetal, metalloid or noble gas.
    11·1 answer
  • PPPPPPPPLLLLLLLLLLLLLLZZZZZZZZZZ HELP ME ITS ALREDY OVER DUE PLZ HELP ME PPPLLLZZZ I NEED IT IM DESPRET
    12·2 answers
  • Which is a possible heat capacity for a bomb calorimeter?
    7·1 answer
  • ________ is defined as a method of preparing cocaine as a chemical substance so that it can be smoked.
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!