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
melomori [17]
3 years ago
7

An analytical chemist is titrating 118.3 mL of a 0.3500 M solution of butanoic acid (HC3H7CO2) with a 0.400 M solution of KOH. T

he pKa of butanoic acid is 4.82. Calculate the pH of the acid solution after the chemist has added 115.4 mL of the solution to it. Note for advanced students: you may assume the final volume equals the initial volume of KOH the solution plus the volume of solution added. Round your answer to 2 decimal places.
Chemistry
1 answer:
TEA [102]3 years ago
4 0

Answer:

pH = 12.33

Explanation:

Lets call HA = butanoic acid and A⁻ butanoic acid and its conjugate base butanoate respectively.

The titration reaction is

HA + KOH ---------------------------- A⁻ + H₂O + K⁺

number of moles of HA :   118.3 ml/1000ml/L x 0.3500 mol/L = 0.041 mol HA

number of  moles of OH  : 115.4 mL/1000ml/L x 0.400 mol/L  = 0.046 mol A⁻

therefore the weak acid will be completely consumed and what we have is  the unreacted strong base KOH which will drive the pH of the solution since the contribution of the conjugate base is negligible.

n unreacted KOH = 0.046 - 0.041 = 0.005 mol KOH

pOH = - log (KOH)

M KOH = 0.005 mol / (0.118.3 +0.1154)L = 0.0021 M

pOH = - log (0.0021) = 1.66

pH = 14 - 1.96 = 12.33

Note: It is a mistake to ask for the pH of the <u>acid solutio</u>n since as the above calculation shows we have a basic solution the moment all the acid has been consumed.

You might be interested in
The reaction between iron(II) oxide and carbon monoxide produces iron and carbon dioxide. How many moles of iron can be obtained
My name is Ann [436]

Answer:

4.75 moles of Fe

Explanation:

We'll begin by writing the balanced equation for the reaction. This is given below:

FeO + CO —> Fe + CO2

Now, we can determine the number of mole of iron, Fe produced by the reaction of 4.75 mol of FeO with excess CO as follow:

From the balanced equation above,

1 mole of FeO reacted to produce 1 mole of Fe.

Therefore, 4.75 moles of FeO will also react to produce 4.75 moles of Fe.

Therefore, 4.75 moles of Fe is produced.

4 0
3 years ago
State whether the error introduced by each of the following problems would result in a high or a low value for the Cu recovery o
vampirchik [111]

Answer:

Low value for copper recovery

Explanation:

The percentage recovery is obtained from;

Percent recovery = amount of substance you actually collected / amount of substance you were supposed to collect × 100

Note that the fact that some of the copper nitrate solution splashed out of the beaker means that some amount copper has been lost from the system. This loss of copper leads to a lower value of copper recovered from solution.

5 0
3 years ago
The ____ connects the left and right sides of the cerebrum
Fofino [41]

Answer:

The left and right hemispheres of the cerebrum are connected by the Corpus Collosum.

Explanation:

The corpus collosum is a thick band of neurons that divides the cerebral cortex lobes into the left and right hemisphere. The corpus callosum allows for both hemispheres to communicate and transfer information! The primary function of the corpus callosum is to integrate sensory, motor, and cognitive performance between the cerebral cortex.  

Ins severe cases of epileptic seizures, a corpus callosotomy is performed, which cuts the corpus callosum in half. This prevents the seizures from becoming more severe, and the brain can reprogram, through neuroplasticity.

3 0
3 years ago
What coefficient for O2 demonstrates the law of conservation of mass?
olga2289 [7]

Answer:

2

Explanation:

The coefficient for O is 2 and this is an example of a combustion reaction. With the help of the coefficient 2 infront of oxygen, this equation now demonstrates law of conservation of mass.

6 0
3 years ago
Select the correct answer.
Nitella [24]

Answer:

C.

Explanation:

Iron is most likely to form a precipitation reaction.

8 0
3 years ago
Other questions:
  • If the half-life of technitium-104 is 18.0 min, how much of a 14.2-g sample will remain after 72 minutes?
    12·2 answers
  • Ice will ________ in water.<br> A. float<br> B. sink<br> C. stay the same
    7·2 answers
  • Help me for number 8 and 9
    9·1 answer
  • Which forms of energy are used when: (a) you ride in an automobile? (b) you bounce a basketball? (c) you boil water to make hot
    15·1 answer
  • Which is the best pure substance gold or air?
    6·2 answers
  • Predict the electronegativity of the undiscovered element with Z=119.
    11·1 answer
  • Which of the following stages would come first in the life of a star? Neutron star White dwarf Protostar Black hole
    9·1 answer
  • Does hydrogen builds all the acids??​
    14·1 answer
  • What is the mass of a object if it occupies a volume of 3.10 cm and has a density of 2.7 g/cm
    5·1 answer
  • Given the following equation: 2 KClO 3 --&gt; 2 KCl + 3 O 2
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!