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
Rudiy27
2 years ago
8

0.53g of acetanilide was subjected to kjeldahl determination and the ammonia produced was collected in 50cm3 of 0.50M of h2so4.o

n dilution 250cm3, the acid was titrated against 25cm3 portion of 0.05M sodium carbonate solution. 13.60 of acid was required for each titration. What is percentage of nitrogen in acetanilide ​
Chemistry
1 answer:
Lady bird [3.3K]2 years ago
7 0

Answer:

10.57% of N in acetanilide

Explanation:

All nitrogen in the sample is converted in NH₃ in the Kjeldahl determination. The NH₃ reacts with H₂SO₄ as follows:

2NH₃ + H₂SO₄ → 2NH₄⁺ + SO₄²⁻

The acid in excess in titrated with Na₂CO₃ as follows:

Na₂CO₃ + H₂SO₄ → Na₂SO₄ + H₂O + CO₂

To solve this question we must find the moles of sodium carbonate = Moles of H₂SO₄ in excess. The added moles - Moles in excess = Moles of sulfuric acid that reacts:

<em>Moles Na₂CO₃ anf Moles H₂SO₄ in excess:</em>

0.025L * (0.05mol / L) = 1.25x10⁻³ moles Na₂CO₃ / 0.01360L =

0.09191M * 0.250L = 0.0230 moles H₂SO₄ in excess.

<em>Moles H₂SO₄ added:</em>

0.050L * (0.50mol / L) = 0.0250 moles H₂SO₄ added

<em>Moles that react:</em>

0.0250 moles - 0.0230 moles = 0.0020 moles H₂SO₄

<em>Moles of NH₃ = Moles N:</em>

0.0020 moles H₂SO₄ * (2mol NH₃ / 1mol H₂SO₄) = 0.0040 moles NH₃ = Moles N

<em>mass N and mass percent:</em>

0.0040 moles N * (14g / mol) = 0.056gN / 0.53g * 100 =

<h3>10.57% of N in acetanilide</h3>
You might be interested in
What is the pH of a 6.7 x 10^−5 M H+ solution?
lyudmila [28]

Answer:

pH = 4.17

Explanation:

According to the molar concentration you stated, pH of the solution is: 4.17

Remember that pH = - log [H⁺]

and [H⁺] = 10^-pH

When:

pH > 7 →  Basic solution

pH = 7 → Neutral solution

pH < 7 → Acid solution

3 0
3 years ago
Read 2 more answers
Saponification is a chemical reaction _____. A. due to the presence of a strong organic acid. B. that results in an alcohol and
dezoksy [38]

Answer:

that results in an alcohol and a carboxylic acid.

Explanation:

Saponification is a chemical reaction process of alkaline hydrolysis of esters(R'COOR group) by which soap is obtained.

For Example, when a base such as sodium hydroxide [NaOH]  is used to hydrolyze an ester, the products are a carboxylate salt and an alcohol. Because soaps are prepared by the alkaline hydrolysis of fats and oils.

In a saponification reaction, alkaline hydrolysis of fats and oils with sodium hydroxide  yields propane-1,2,3-triol and the corresponding sodium salts of the component fatty acids.

i.e  Fat or oil + caustic alkali ⇒ Soap + propane-1,2,3-triol

As a specific example, ethyl acetate and NaOH react to form sodium acetate and ethanol:

The reaction goes to completion in the image below:

8 0
3 years ago
Which keystone species feed on other animals and prevent them from damaging the ecosystem?
Arisa [49]
Predators? I just looked it up lol
8 0
2 years ago
A 40.0-L sample of fluorine is heated from 90.0°C to 186.0°C. What volume will the sample occupy at the higher temperature?
jasenka [17]

Answer:

The volume will be 82.67 L

Explanation:

Charles's Law is the relationship between the volume and temperature of a certain amount of ideal gas. In this way, Charles's law is a law that says that when the amount of gas and pressure are kept constant, the ratio between volume and temperature will always have the same value:

\frac{V}{T} = k

Having a certain volume of gas V1 that is at a temperature T1 at the beginning of the experiment, by varying the volume of gas to a new value V2, then the temperature will change to T2, and it will be true:

\frac{V1}{T1} =\frac{V2}{T2}

In this case, you know:

  • V1= 40 L
  • T1= 90 °C
  • V2= ?
  • T2= 186 °C

Replacing:

\frac{40L}{90C} =\frac{V2}{186 C}

Solving:

V2=\frac{40L}{90C} *186 C

V2= 82.67 L

<u><em>The volume will be 82.67 L</em></u>

5 0
3 years ago
What is the valence of oxygen
leva [86]

Answer:

-2

Explanation:

eACH ELEMENT HAS AN SPECIFIC VALENCE, FOR EXAMPLE, CARBON (+2),+4 IN THE CASE OF OXYGEN IS -2

7 0
3 years ago
Other questions:
  • Sodium phosphate dodecahydrate, na3po4(12h2o), is crystalline salt that is water soluble. describe what is present in an aqueous
    15·1 answer
  • Which statement is true for the highest point of a projectile trajectory?
    10·2 answers
  • A covalent bond is likely to be polar when ________. one of the atoms sharing electrons is more electronegative than the other a
    9·1 answer
  • The mole fraction of hcl in a solution prepared by dissolving 5.5 g of hcl in 200 g of c2h6o is ________. the density of the sol
    8·1 answer
  • What is the mole fraction of Ba(OH)2 in an aqueous solution that contains 22.8% Ba(OH)2 by mass?
    8·1 answer
  • What are molecules and what are they made of?
    13·1 answer
  • Sodium and ____ are the two primary electrolytes.Question 5 options:
    9·1 answer
  • A diagram of the areas surrounding the Gulf of Mexico is provided. A hurricane that comes in from the Gulf of Mexico will most l
    7·1 answer
  • Identify each description as either a physical or chemical change.
    10·1 answer
  • Naming compounding<br> N2O
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!