22.05.2022

# A student has synthesized a new compound (compound A, a nonelectrolyte). She uses osmotic pressure to determine the molar mass of compound A. She dissolves 0.50 g of compound A in water and prepares 15 mL of solution. At 25 C the osmotic pressure is 7.38 atm. Calculate the molar mass (g/mole) of compound A. Do not include a unit with your answer.

0

24.06.2023, solved by verified expert

110g/mol is the molar mass of compound A

Explanation:

The osmotic pressure of a solution could be obtained using the equation:

π = i*M*R*T -Solving molarity we can find the molar mass of the solute A-

Where π is osmotic pressure (7.38atm)

i is Van't Hoff's factor (1 for nonelectrolytes)

M is molarity (Our incognite)

R is gas constant (0.082atmL/molK)

T is absolute temperature (25°C + 273.15 = 298.15K)

Computing the values:

7.378atm = 1*M*0.082atmL/molK*298.15K

0.3018 mol/L is the concentration of the solution.

The volume of the solution is 15mL = 0.015L. Moles of the solute are:

0.3018 mol/L * 0.015L = 4.527x10⁻³ moles

Molar mass is the ratio between mass of the compound (0.50g) and the moles (4.527x10⁻³ moles). That is:

0.50g / 4.527x10⁻³ moles =

110g/mol is the molar mass of compound A

### Faq

Chemistry

110g/mol is the molar mass of compound A

Explanation:

The osmotic pressure of a solution could be obtained using the equation:

π = i*M*R*T -Solving molarity we can find the molar mass of the solute A-

Where π is osmotic pressure (7.38atm)

i is Van't Hoff's factor (1 for nonelectrolytes)

M is molarity (Our incognite)

R is gas constant (0.082atmL/molK)

T is absolute temperature (25°C + 273.15 = 298.15K)

Computing the values:

7.378atm = 1*M*0.082atmL/molK*298.15K

0.3018 mol/L is the concentration of the solution.

The volume of the solution is 15mL = 0.015L. Moles of the solute are:

0.3018 mol/L * 0.015L = 4.527x10⁻³ moles

Molar mass is the ratio between mass of the compound (0.50g) and the moles (4.527x10⁻³ moles). That is:

0.50g / 4.527x10⁻³ moles =

110g/mol is the molar mass of compound A
Chemistry
Explanation: Convert 30 ml to l: 30 mL = 0.03 L
Molarity = mol/l
mol = molarity * L
mol = 0.15 * 0.03 = 0.0045 mol
Chemistry
Answer: b. Fiona is correct because the diagram shows two individual simple machines.

Explanation:
A mechanical device using which we can change the direction or magnitude of force applied is known as simple machine.
For example, in the given diagram there are two individual simple machines.
The machine helps in changing the direction or magnitude of force applied by the man. As a result, it becomes easy for him to carry different things easily from one place to another.
Thus, we can conclude that the statement Fiona is correct because the diagram shows two individual simple machines, is correct.
Chemistry

glycoproteins

Explanation:

A positive reaction for Molisch's test is given by almost all carbohydrates (exceptions include tetroses & trioses). It can be noted that even some glycoproteins and nucleic acids give positive results for this test (since they tend to undergo hydrolysis when exposed to strong mineral acids and form monosaccharides).

Chemistry

Taking into accoun the ideal gas law, The volume of a container that contains 24.0 grams of N2 gas at 328K and 0.884 atm is 26.07 L.

An ideal gas is a theoretical gas that is considered to be composed of point particles that move randomly and do not interact with each other. Gases in general are ideal when they are at high temperatures and low pressures.

The pressure, P, the temperature, T, and the volume, V, of an ideal gas, are related by a simple formula called the ideal gas law:

P×V = n×R×T

where P is the gas pressure, V is the volume that occupies, T is its temperature, R is the ideal gas constant, and n is the number of moles of the gas. The universal constant of ideal gases R has the same value for all gaseous substances.

Explanation:

In this case, you know:

P= 0.884 atm

V= ?

n= 0.857 moles (where 28 g/mole is the molar mass of N₂, that is, the amount of mass that the substance contains in one mole.)

R=0.082

T= 328 K

Replacing in the ideal gas law:

0.884 atm×V= 0.857 moles× 0.082 ×328 K

Solving:

V= 26.07 L

The volume of a container that contains 24.0 grams of N2 gas at 328K and 0.884 atm is 26.07 L.

Chemistry
15 moles.Explanation:Hello,In this case, the undergoing chemical reaction is:Clearly, since carbon and oxygen are in a 1:1 molar ratio, 15 moles of carbon will completely react with 15 moles of oxygen, therefore 15 moles of oxygen remain as leftovers. In such a way, since carbon and carbon dioxide are also in a 1:1 molar ratio, the theoretical yield of carbon dioxide is 15 moles based on the stoichiometry:Best regards.
Chemistry
Explanation: Given:
Original amount (N₀) = 100 g
Number of half-lives (n) = 11460/5730 = 2
Amount remaining (N) = ?
N = 1/2ⁿ × N₀
N = 1/2^2 × 100
N = 0.25 × 100
N = 25 g
Chemistry
Answer: The product formed is potassium chloride.
Explanation:
Precipitation reaction is defined as the chemical reaction in which an insoluble salt is formed when two solutions are mixed containing soluble substances. The insoluble salt settles down at the bottom of the reaction mixture.

The chemical equation for the reaction of potassium phosphate and magnesium chloride follows (look at the picture)

2 moles of aqueous solution of potassium phosphate reacts with 3 moles of aqueous solution of magnesium chloride to produce 1 mole of solid magnesium phosphate and 6 moles of aqueous solution of potassium chloride.
Chemistry
Explanation: The other options are incorrect. Let's write the correct formulas:
A. Diarsenic pentoxide - As2O5
C. Sodium dichromate - Na2Cr2O7
D. magnesium phosphide - Mg3P2
Chemistry
b. basic
c. acidic
d. neutral

Explanation: Acids and bases can be classified in terms of hydrogen ions or hydroxide ions, or in terms of electron pairs. (look at the picture)
Let us note that from the pH scale, a pH of;
0 - 6.9 is acidic
7 is neutral
8 - 14 is basic

But pH= - log [H^+]
pOH = -log [OH^-]
Then;
pH + pOH = 14
Hence;
pH = 14 - pOH

a. [H+] = 6.0 x 10-10M
pH= 9.22 is basic
b. [OH-] = 30 × 10-2M
pH = 13.5 is basic
C. IH+1 = 20× 10-7M
pH = 0.56 is acidic
d. [OH-] = 1.0 x 10-7M
pH = 7 is neutral
What is Studen
Studen helps you with homework in two ways:

## Try asking the Studen AI a question.

It will provide an instant answer!

FREE