answer.
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
Alex17521 [72]
2 years ago
3

Oxalic acid is the first in the series of dicarboxylic acids (HOOC-COOH, H2C2O4). It occurs naturally in many plants. Oxalic aci

d content is high in the leaves of rhubarb (we don't eat the leaves because they are poisonous). Calculate the pH of a 0.100 M oxalic acid solution. Ka1 = 5.6x10-2, Ka2 = 5.4x10-5 Enter to 2 decimal places.
Chemistry
1 answer:
Sphinxa [80]2 years ago
5 0

Answer:

pH = 1.28

Explanation:

The Oxalic acid (HOOC-COOH) that is in solution with water follows the equilibrium:

HOOC-COOH(aq) + H₂O(l) ⇄ HOOC-COO⁻(aq) + H₃O⁺(aq)

Where Ka₁ is defined as:

Ka₁ = 5.6x10⁻² = [HOOC-COO⁻] [H₃O⁺] / [HOOC-COOH] <em>(1)</em>

In equilibrium, the concentration of each specie must be:

[HOOC-COOH] = 0.100M - X

[HOOC-COO⁻] = X

[H₃O⁺] = X

Replacing in (1):

5.6x10⁻² = [X] [X] / [0.100 - X]

5.6x10⁻³ - 5.6x10⁻²X = X²

0 = X² + 5.6x10⁻²X - 5.6x10⁻³

Solving for X:

X = -0.1 → False answer, there is no negative concentrations.

X = 0.0519 → Right answer

That means <em>[H₃O⁺] = 0.0519</em>

<em>As pH = -log [H₃O⁺]</em>

<em>pH = 1.28 </em>

You might be interested in
A chemist wants to extract copper metal from copper chloride solution. The chemist places 0.50 grams of aluminum foil in a solut
Irina-Kira [14]

Answer:

Approximately 0.36 grams, because copper (II) chloride acts as a limiting reactant.

Explanation:

  • It is a stichiometry problem.
  • We should write the balance equation of the mentioned chemical reaction:

<em>2Al + 3CuCl₂ → 3Cu + 2AlCl₃.</em>

  • It is clear that 2.0 moles of Al foil reacts with 3.0 moles of CuCl₂ to produce 3.0 moles of Cu metal and 2.0 moles of AlCl₃.
  • Also, we need to calculate the number of moles of the reported masses of Al foil (0.50 g) and CuCl₂ (0.75 g) using the relation:

<em>n = mass / molar mass</em>

  • The no. of moles of Al foil = mass / atomic mass = (0.50 g) / (26.98 g/mol) = 0.0185 mol.
  • The no. of moles of CuCl₂ = mass / molar mass = (0.75 g) / (134.45 g/mol) = 5.578 x 10⁻³  mol.
  • <em>From the stichiometry Al foil reacts with CuCl₂ with a ratio of 2:3.</em>

∴ 3.85 x 10⁻³  mol of Al foil reacts completely with 5.578 x 10⁻³  mol of CuCl₂ with <em>(2:3)</em> ratio and CuCl₂ is the limiting reactant while Al foil is in excess.

  • From the stichiometry 3.0 moles of  CuCl₂ will produce the same no. of moles of copper metal (3.0 moles).
  • So, this reaction will produce 5.578 x 10⁻³ mol of copper metal.
  • Finally, we can calculate the mass of copper produced using:

mass of Cu = no. of moles x Atomic mass of Cu = (5.578 x 10⁻³  mol)(63.546 g/mol) = 0.354459 g ≅ 0.36 g.

  • <u><em>So, the answer is:</em></u>

<em>Approximately 0.36 grams, because copper (II) chloride acts as a limiting reactant.</em>

5 0
2 years ago
The enthalpy change for the explosion of ammonium nitrate with fuel oil is –7198 kJ for every 3 moles of NH4NO3. What is the ent
anastassius [24]

Answer:

−2399.33 kJ

Explanation:

If NH₄NO₃ reacts with fuel oil to give a ΔH of -7198 for every 3 moles of NH₄NO₃

What is the enthalpy change for 1.0 mole of NH₄NO₃ in this reaction

∴ For every 1 mole, we will have \frac{1}{3} of the total enthaply of the 3 moles

so, to determine the 1 mole; we have:

\frac{1}{3}*(-7198kJ)

= −2399.33 kJ

∴ the enthalpy change for 1.0 mole of NH₄NO₃ in this reaction = −2399.33 kJ

7 0
2 years ago
The symbol P represents the element phosphorus. This element’s atomic number is 15. How many protons and electrons are in a P–3
Leno4ka [110]
A charge of -3 means it gained 3 electrons meaning electrons would go from 15 to 18 because protons and electrons are the same and you start with 15.
So your answer is 15 protons, 18 electrons
7 0
2 years ago
Read 2 more answers
Your task is to measure the amount of energy evolved during the combustion of some hydrocarbon. Which of the following would be
Dahasolnce [82]

Answer:

c. Bomb calorimetry

Explanation:

The hydrocarbons are combustibles, it means that they can react in a combustion reaction to release energy. To measure this amount of energy, it's necessary equipment that the reaction can be placed in a controlled way. The bomb calorimeter is this equipment, which is an adiabatic vessel, with water. The heat is calculated based on the increase in the water temperature.

The coffee-cup calorimetry is used to measure the heat of a dissolution reaction and the bomb manometry is used to measure the pressure.

7 0
2 years ago
Select the true statements about denaturation.
fiasKO [112]

Answer:

The correct options are: Denaturation of an enzyme will cause a loss of its catalytic activity.

Egg white meringue contains denatured egg white proteins.

A denatured protein has a different tertiary structure than its native state.

 Protein denaturation involves cleavage of its peptide bonds.

Explanation:

Protein denaturation is the breakdown of tertiary or quaternary junctions of proteins, which are the easiest to break compared to primary and secondary.

Denaturation can arise due to a change in pH or due to excess temperature. An enzyme is generally a protein and if it is subjected to acidic acids or high temperatures, it denatures, ceasing to perform its function.

Zymogen is a non-denatured INACTIVE proenzyme, that is why we consider that option false along with those that were not selected.

5 0
2 years ago
Other questions:
  • Calculate the frequency of the n = 6 line in the Lyman series of hydrogen.
    15·2 answers
  • Josh is studying pH calculations and tests a basic solution with a pH meter. He finds that the solution has a pH equal to 9.2. W
    15·1 answer
  • Copper has a face-centered cubic unit cell. the density of copper is 8.96 g/cm3. calculate a value for the atomic radius of copp
    9·1 answer
  • Describe the pattern of the lewis dot structure of the first 18 elements
    14·1 answer
  • To maximize the yield in a certain manufacturing process, a solution of a weak monoprotic acid that has a concentration between
    6·1 answer
  • A 0.050 M solution of AlCl3 had an observed osmotic pressure of 3.85 atm at 20 ∘C . Calculate the van't Hoff factor i for AlCl3.
    10·1 answer
  • A phosphorus atom with 4 bonds has a charge of ___.
    6·1 answer
  • Can 1750 mL of water dissolve 4.6 moles of Copper Sulfate CuSO4? _________ Why? / Why not?
    8·1 answer
  • Predict the initial and isolated products for the reaction. The starting material is a 6 carbon chain where there is a triple bo
    10·1 answer
  • Please help like now please
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!