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
ehidna [41]
3 years ago
8

Determine the acid dissociation constant for a 0.020 m formic acid solution that has a ph of 2.74. formic acid is a weak monopro

tic acid and the equilibrium equation of interest is hcooh(aq) + h2o(l) ⇌ h3o+(aq) + hco2-(aq). enter your answer in exponential (e) format (sample 1.23e-4) with two decimal places and without units.
Chemistry
1 answer:
Setler [38]3 years ago
7 0

Answer:

Ka = 1.82x10⁻⁴

Explanation:

To solve this problem, we need a basis. In this case, we need the overall reaction and a ICE chart. So, let's write the overall reaction first:

HCOOH + H₂O <--------> H₃O⁺ + HCOO⁻    Ka = ?

Now that we have the overall reaction, we need to write the ICE chart. In this way we can determine what data do we have, and what do we have left to determine:

      HCOOH + H₂O <--------> H₃O⁺ + HCOO⁻    Ka = ?

i)        0.02                                0             0

e)       0.02-x                             x              x

The Ka expression is:

Ka = [H₃O⁺] [HCOO⁻] / [HCOOH]

Replacing the given data we have:

Ka = x² / 0.02 - x

Now, the value of x can be calculated because we already have the pH of the formic acid, and with it, we can calculate the [H₃O⁺] with the following expression:

[H₃O⁺] = 10^(-pH)

Replacing we have:

[H₃O⁺] = 10^(-2.74) = 1.82x10⁻³ M

This is the value of x, so replacing in the Ka expression, we can calculate then, the value of Ka:

Ka = (1.82x10⁻³)² / (0.02 - 1.82x10⁻³)

<h2>Ka = 1.82x10⁻⁴</h2>
You might be interested in
Pls help asap pls !!
klio [65]

Answer:

basic solution.

Explanation:

has a pH of 12.

it turns clear indicator pink.

it contains hydroxide ions which conduct electricity

3 0
3 years ago
Newton’s second law of motion is F=ma A net force of 60 N north acts on an object with a of 30 kg. Use Newton’s second law of mo
horsena [70]
I’m pretty sure the immediate answer is 2. Using the equation 60N=(30kg)x2(whatever unit of measure) also it will change because if you change the mass or the Net Force, your going to have to redo the equation based on the new information.
8 0
3 years ago
Read 2 more answers
Rank these acids according to their expected pKa values.ClCH2COOHClCH2CH2COOHCH3CH2COOHCl2CHCOOHIn order of highest pka to lowes
Ilia_Sergeevich [38]

Answer:

CH₃CH₂CH₂COOH > CH₃CH₂COOH > ClCH₂CH₂COOH  > ClCH₂COOH

Explanation:

Electron-withdrawing groups (EWGs) increase acidity by inductive removal of electrons from the carboxyl group.

Electron-donating groups (EDGs) decrease acidity by inductive donation of electrons to the carboxyl group.

  • The closer the substituent is to the carboxyl group, the greater is its effect.
  • The more substituents, the greater the effect.  
  • The effect tails off rapidly and is almost zero after about three C-C bonds.

CH₃CH₂-CH₂COOH —  EDG —                         weakest —  pKₐ = 4.82

      CH₃-CH₂COOH — reference —                                     pKₐ = 4.75

  ClCH₂-CH₂COOH — EWG on β-carbon— stronger —     pKₐ = 4.00

           ClCH₂COOH — EWG on α-carbon — strongest —  pKₐ = 2.87

6 0
2 years ago
Read 2 more answers
A metal (M) forms an oxide with the formula MO. If the oxide contains 7.17 % O by mass, what is the identity of the metal?
Nataly_w [17]

The metal is lead, Pb.

One unit of the oxide contains one atom of O (16.00 u).

∴ Mass of oxide = 16.00 u O × (100 u MO/7.17 u O) = 223.15 u MO

Mass of M = mass of MO – mass of O = 223.15 u -16.00 u = 207.2 u

The only element with an atomic mass of 207.2 u is lead (Pb) and the formula of the oxide is PbO.

7 0
3 years ago
Is a bag of different colored jelly beans a solution or a mixture
Sladkaya [172]

Answer:

a mixture

Explanation:

hope this helps

6 0
3 years ago
Read 2 more answers
Other questions:
  • Instrumental methods need only a microscopic sample to return an accurate result. Why is this so?
    7·1 answer
  • What is the definition of plate tectonics?
    7·2 answers
  • Which statement best describes why carbon can form a wide variety of organic compounds?
    12·2 answers
  • What is the correct name for the compound mn 3(po 4)2manganese (ii) phosphatemanganese phosphatemanganese (i) phosphate manganes
    14·1 answer
  • If 3.64g of sand is separated from 5.25g of a mixture of salt and sand what is the percentage of sand in the sample
    15·1 answer
  • Why Chlorine gas used in ww1
    9·1 answer
  • If 4.0 mol aluminum and 7.0 mol hydrogen bromide react according to the following equation, how many moles of hydrogen are forme
    15·1 answer
  • If 36 000 kg of full cream milk containing 4% fat is to be separated in a 6 hour period into skim milk with 0.45% fat and cream
    14·1 answer
  • An ionic compound contains an unknown ion X and has the formula X3N2. Ion X contains 10 electrons. Write down the chemical symbo
    9·1 answer
  • How to frick a chicken...
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!