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
Ksenya-84 [330]
3 years ago
14

Three mixtures were prepared from three very narrow molar mass distribution polystyrene samples with molar masses of 10,000, 30,

000 and 100,000 g mol−1 as indicated below: (a) Equal numbers of molecules of each sample (b) Equal masses of each sample (c) By mixing in the mass ratio 0.145:0.855 the two samples with molar masses of 10,000 and 100,000 g mol−1 For each of the mixtures, calculate the number-average and weight-average molar masses and comment upon the meaning of the values.
Chemistry
1 answer:
8_murik_8 [283]3 years ago
6 0

Answer:

(a). 46,666.7 g/mol; 78,571.4 g/mol

(b). 86950g/mol; 46,666.7 g/mol.

(c). 86950g/mol; 43,333.33 g/mol

Explanation:

So, we are given the molar masses for the three samples as: 10,000, 30,000 and 100,000 g mol−1.

Thus, the equal number of molecule in each sample = ( 10,000 + 30,000 + 100,000 ) / 3 = 46,666.7 g/mol.

The average molar mass = [ ( 10,000)^2 + (30,000)^2 + 100,000)^2] ÷ 10,000 + 30,000 + 100,000 = 78,571. 4 g/mol.

(b). The equal masses of each sample = 3/[ ( 1/ 10,000) + (1/30,000 ) + (1/100,000) ] = 20930.23 g/mol.

Average molar mass = ( 10,000 + 30,000 + 100,000 ) / 3 = 46,666.7 g/mol.

(c). Equal masses of the two samples = (0.145 × 10,000) + (0.855 × 100,000)/ 0.145 + 0.855 = 86950g/mol.

The weight average molar mass = 1.7 + 10,000 + 100,000/ 1.7 + 1 = 43,333.33 g/mol.

You might be interested in
May someone help me with these questions it is only 2
garri49 [273]
Most likely decreased birth rate and increased emigration.
6 0
3 years ago
If you were to react 4.3 miles of magnesium phosphide how many moles of potassium would you need?
bixtya [17]

Answer:

25.8

Explanation:

Let's write the reaction between magnesium-phosphide and potassium:

Mg3P2 + K = Mg + K3P

And now let's balance this equation:

Mg3P2+6K=3Mg+2K3P

We see that the ratio of magnesium-phosphide and potassium is 1:6, which means that for every mole of magnesium-phosphide there need to be 6 moles of potassium.

Since we have 4.3 moles of Mg3P2, there need to be 6 • 4.3 = 25.8 moles of potassium.

5 0
2 years ago
Which one of the following is not a property of a base?
AlekseyPX

Answer:

option B is correct

Explanation:

5 0
3 years ago
Which describes any substance that shatters or breaks easily?
Daniel [21]

Answer:

Brittle

Explanation:

3 0
3 years ago
Read 2 more answers
A container with a fixed volume, filled with hydrogen gas at -104°C and 71.8 K PA is heated until the pressure reaches 225.9 K P
Daniel [21]

Answer:

The correct answer is 532 K

Explanation:

The Gay-Lussac law describes the behavior of a gas at constant volume, by changing the pressure or temperature. When is heated, the change in pressure of the gas is directly proportional to it absolute temperature (in Kelvin or K).

We have the following initial conditions:

P1= 71.8 kPa

T1= -104ºC +273 = 169 K

If the pressure increases until reaching 225.9 kPa (P2), we can calculate the final temperature of the gas (T2) by using the Gay-Lussac derived expression:

P1 x T2 = P2 x T1

⇒T2= (P2 x T1)/P1 = (225.9 kPa x 169 K)/71.8 kPa= 531.7 K ≅ 532 K

4 0
3 years ago
Other questions:
  • Explain the difference between a physical property and a chemical property
    11·1 answer
  • How does the weight of your skin compare to the weight of your brain
    6·1 answer
  • How many electrons does the predictable (most common) ion of calcium contain?
    14·1 answer
  • Both Jacques Charles and Joseph Louis Guy-Lussac were avid balloonists. In his original flight in 1783, Jacques Charles used a b
    7·1 answer
  • The name of the METAL in an ionic compounds does not change<br><br> True or False
    6·1 answer
  • Power plants use specialized scrubbers to remove sulfur oxide gases. true or false.
    13·2 answers
  • Calculate the ratio of the effusion ratesbetween chlorine gas (Cl2, molar mass = 71 g/mol) and iodine gas(I2, molar mass = 254 g
    5·1 answer
  • All living things are made of​
    14·2 answers
  • chemist must prepare of hydrochloric acid solution with a pH of at . He will do this in three steps: Fill a volumetric flask abo
    6·1 answer
  • Infer Xenon, a nonreactive gas used in strobe lights, is a poor conductor of heat and electricity. Would you expect xenon to be
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!