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
Varvara68 [4.7K]
3 years ago
15

The concentration of urea in a solution prepared by dissolving 16 g of urea in 20 g of H2OH2O is ________% by mass. The molar ma

ss of urea is 60.0 g/mol. The concentration of urea in a solution prepared by dissolving 16 g of urea in 20 g of is ________% by mass. The molar mass of urea is 60.0 g/mol. 44 80 0.80 0.48 0.44
Chemistry
1 answer:
Arada [10]3 years ago
4 0

Answer:

44

Explanation:

Given that :

Mass of solute = Mass of urea = 16g

Mass of water = 20g

Mass of solution = (mass of solute + mass of solvent) = (mass of urea + mass of water) = (16g + 20g) = 36g

Percentage Mass = (mass of solute / mass of solution) * 100%

Percentage Mass = (16 / 36) * 100%

Percentage Mass = 0.4444444 x 100%

Percentage Mass = 44.44%

Percentage Mass = 44%

You might be interested in
What type of forest would you find south of spruce
yanalaym [24]
<span>The correct answer should be Oak becaue of the climate. Spruces usually grow in places that are really cold, the more north you go the higher the chance of finding a spruce forest. South of it is usually an Oak forest because the climate is warmer and oaks grow in warmer climates that are not as harsh as those with spruces.</span>
4 0
3 years ago
6. 100 ml of gaseous hydrocarbon consumes 300
mario62 [17]

Answer:

  • <u><em>a. C₂H₄</em></u>

Explanation:

At constant pressure and temperature, the mole ratio of the gases is equal to their volume ratio (a consequence of Avogadro's law).

Hence, the <em>complete combustion reaction</em> that has a ratio of 100 ml of gaseous hydrocarbon to 300 ml of oxygen, is that whose mole ratio is 1 mol hydrocarbon : 3 mol of oxygen.

Then, you must write the balanced chemical equations for the complete combustion of the four hydrocarbons in the list of choices, and conclude which has such mole ratio (1 mol hydrocarbon : 3 mol oxygen).

A complete combustion reaction of a hydrocarbon is the reaction with oxygen that produces CO₂ and H₂O, along with the release of heat and light.

<u>a. C₂H₄:</u>

  • C₂H₄ (g) + 3O₂ (g) → 2CO₂(g)  + 2H₂O (g)

Precisely, for this reaction the mole ratio is 1 mol C₂H₄: 2 mol O₂, hence, this is the right choice.

The following analysis just shows that the other options are not right.

<u>b. C₂H₂:</u>

  • 2C₂H₂ (g) + 5O₂ (g) → 4CO₂(g)  + 2H₂O (g)

The mole ratio for this reaction is 2 mol C₂H₂ :5 mol O₂.

<u>с. С₃Н₈</u>

  • C₃H₈ (g) + 5O₂ (g) → 3CO₂(g)  + 4H₂O (g)

The mole ratio is 1 mol C₃H₈ : 5 mol O₂

<u>d. C₂H₆</u>

  • 2C₂H₆ (g) +7 O₂ (g) → 4CO₂(g)  + 6H₂O (g)

The mole ratio is 2 mol C₂H₆ : 7 mol O₂

7 0
4 years ago
Barium has a body-centered cubic structure. If the atomic radius of barium is 222 pm, calculate the density of solid barium?
Flauer [41]

Answer: density =3.377g/cm³

Explanation:

Density =( molecular weight × effective number of atoms per unit cell) / (volume of unit cell × avogadro constant)

D= (M ×n) /(V×A)

M= 137g/mol

n= 2 (For BCC)

V=a³ , where a= 4r/√3

a= (4×222)/√3

a=512.69pm

a= 512.69×10^-10cm

V= ( 512.69×10^-10)^3

V= 1.3476×10^-22cm³

D= (137×2)/(1.3476×10^-22 × 6.02^23)

D= 3.377g/cm³

Therefore the density of barium is 3.377g/cm³

5 0
3 years ago
How are industrial and agricultural pollution similar?
Norma-Jean [14]

Answer:

Both of them are polluting the environment. Industrial pollution is the pollution caused from industries and it can be in different forms such as water waster or air pollution. Agricultural pollution is caused from plants or crops that are grown by the farmers. For example, pesticides that may ruin the soil and is dangerous for our environment.

Explanation:

6 0
3 years ago
Initially, 0.65 mol of PCl5 is placed in a 1.0 L flask. At equilibrium, there is 0.15 mol of PCl3 in the flask. What is the equi
borishaifa [10]

Answer : The equilibrium concentration of PCl_5 is, 0.50 M

Explanation : Given,

Initial moles of PCl_5 = 0.65 mole

Volume of solution = 1.0 L

Moles of PCl_3 at equilibrium = 0.15 mole

The balanced equilibrium reaction will be,

                          PCl_5\rightleftharpoons PCl_3+Cl_2

Initial moles     0.65        0         0

At eqm.           (0.65-x)     x         x

Moles of PCl_3 at equilibrium = x = 0.15 mole

Moles of Cl_2 at equilibrium = x = 0.15 mole

Moles of PCl_5 at equilibrium = (0.65-x) = (0.65-0.15) = 0.50 mole

Now we have to calculate the concentration of PCl_3,Cl_2\text{ and }PCl_5 at equilibrium.

Formula used : Concentration=\frac{Moles}{Volume}

\text{Concentration of }PCl_3=\frac{\text{Moles of }PCl_3}{\text{Volume of solution}}=\frac{0.15mole}{1.0L}=0.15M

\text{Concentration of }Cl_2=\frac{\text{Moles of }Cl_2}{\text{Volume of solution}}=\frac{0.15mole}{1.0L}=0.15M

\text{Concentration of }PCl_5=\frac{\text{Moles of }PCl_5}{\text{Volume of solution}}=\frac{0.50mole}{1.0L}=0.50M

Therefore, the equilibrium concentration of PCl_5 is, 0.50 M

8 0
4 years ago
Other questions:
  • A birthday balloon had a volume of 14.1 L when the gas inside was at a temperature of 13.9 °C. Assuming no gas escapes, what is
    14·1 answer
  • Plz help need help fast what is the name of the theory that sciencetist have developed to explain the formaton of the universe
    10·2 answers
  • What elements react the most? Like have the most reactivity.
    12·1 answer
  • Jack tries to place magnets on the door of his refrigerator. He observes that the magnets don't stick. He guesses that the door
    8·2 answers
  • What are the products of cyclic electron flow during the light reactions of photosynthesis?
    12·1 answer
  • Arcylonitrile, c3h3n, is the starting material for the production of a synthetic fiber and can be made from propylene, c3h6, rea
    11·1 answer
  • E28.12.) When 229 ) of energy is supplied as heat at constant pressure to 3.0 mol Ar(g) the temperature of the sample increases
    9·1 answer
  • Over time, pressure and heat change limestone into marble. This change is from:
    14·1 answer
  • Why is it important to be careful when walking on an icy sidewalk?
    5·2 answers
  • Chemistry students were testing compounds in an aqueous solution to see which one had the strongest electrical current. There ar
    10·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!