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
Lana71 [14]
3 years ago
12

A 30.0-mL sample of 0.165 M propanoic acid is titrated with 0.300 M KOH.

Chemistry
1 answer:
Svetach [21]3 years ago
5 0

Answer:

1) pH = 4.51

2) pH = 4.87.

3) pH = 12.32

Explanation:

1) the Ka of propanoic acid is 1.34 X 10⁻⁵

Therefore pKa = 4.87

When we add 5 mL of 0.300 M NaOH the moles of base added is

moles = molarity X volume

moles = 0.300 X 5mL = 1.5 mmoles

moles of acid present = molarity X volume = 0.165 X 30.0 = 4.95 mmoles

on addition of 1.5 mmoles of base the moles of acid neutralized = 1.5mmole

This will result in formation of salt of the acid

the moles of salt formed = 1.5 mmoles

the moles of acid left = 4.95 - 1.5 = 3.45 mmol

this acid and its salt mixture results in formation of a buffer

the pH of buffer is calculated as:

pH = pKa + log [salt] / [acid]

pH = 4.87 + log [1.5/3.45] = 4.51

2) at half equivalence point the moles of acid becomes equal to moles of salt formed thus the pH of solution will become equal to the pKa of acid

pH = 4.87.

3) the moles of based added due to addition of 20.0 mL = molarity X volume

moles = 0.300 X 20 = 6mmol

This will completely neutralize the acid (4.95 mmol)

after neutralization the moles of base left = 6-4.95 = 1.05 mmol

Total volume of solution  = volume of acid + volume of base =30+20=50

concentration of hydroxide ion (due to excess base) = \frac{mmoles}{volume(mL)}

[OH⁻]=0.021

pOH = -log[OH⁻]=1.68

pH = 14-pOH = 12.32

You might be interested in
If 61.5 moles of an ideal gas occupies 97.5 liters at 473 K, what is the pressure of the gas, in mmHg?
kiruha [24]
I’d say for the answer 13.13 mmHg?
5 0
2 years ago
20 POINTS I will give brainliest to whoever answers correctly
Romashka [77]

All organisms need four types of organic molecules: nucleic acids, proteins, carbohydrates and lipids; life cannot exist if any of these molecules are missing.

6 0
2 years ago
Review this reaction:H2SO4 + NaOH ?.What are the product(s)?Na2SO4H2ONa2SO4 and H2ONaH and SO4OHH3SO5
muminat

i think its MIDDLE FINGERS UP IN THE SKY AND AT THESE AHOLE MODERATORS

6 0
3 years ago
Read 2 more answers
Formula for the compound that contains Mg2+ and O2-
jeka94

Answer:

MgO.

Explanation:

charges of both satisfy one another (balanced) -- producing a compound MgO.

7 0
2 years ago
High-pressure liquid chromatography (HPLC) is a method used in chemistry and biochemistry to purify chemical substances. The pre
kotykmax [81]

Answer:

3.41 x10⁶ torr

Explanation:

To solve this problem we need to remember the equivalency:

1 torr = 133.322 Pa

Then we can proceed to<u> convert 4.55×10⁸ Pa into torr.</u> To do that we just need to multiply that value by a fraction number, putting the unit that we want to convert <em>from</em> in the <em>denominator</em>, and the value we want to convert <em>to</em> in the <em>numerator</em>:

4.55x10⁸ Pa * \frac{1torr}{133.322Pa} = 3.41 x10⁶ torr

6 0
3 years ago
Other questions:
  • How many molecules of ethanol (c2h5oh) (the alcohol in alcoholic beverages) are present in 160 ml of ethanol? the density of eth
    8·1 answer
  • Acid hydrolase, a digestive enzyme, would most likely be found in which organelle?
    12·2 answers
  • I ONLY NEED 1 EXAMPLE for each one PLZ HELP ME I WILL MAKE BRAINLIST HELP ME FAST PLZ!!!! Using a skillet on the stove to cook s
    5·2 answers
  • What is the shape of pure carbon fullerenes?
    15·1 answer
  • What is true of neutrons?
    11·1 answer
  • At what temperature does uranium hexafluoride have a density of 0.5820 g/L at 0.5073 atm?
    6·1 answer
  • What is the freezing point (in °C) of a 0.743 m
    12·1 answer
  • What is the molar mass of the EF?
    15·2 answers
  • A common oxidizing agent is..?
    5·1 answer
  • How many molecules of water in 61.0 grams of h2o​
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!