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
Diano4ka-milaya [45]
3 years ago
7

When 12.71 g of copper react with 8.000 g of sulfur, 14.72 g of copper(I) sulphide is produced. What is the percentage yield in

this reaction?
2Cu(s) + S(g) → Cu2S(s)
Show your work.
Chemistry
1 answer:
Citrus2011 [14]3 years ago
5 0
2Cu + S = Cu₂S

n(Cu)=m(Cu)/M(Cu)
n(Cu)=12.71/63.55=0.2 mol

n(S)=m(s)/M(S)
n(S)=8.000/32.01=0.25 mol

Cu:S  2:1  
0.2 mol : 0.25 mol copper deficiency, sulphur in excess

theoretical mass of copper (I) sulfide 
m(Cu₂S)=M(Cu₂S)n(Cu)/2

the percentage yield in the reaction is
w=m'(Cu₂S)/m(Cu₂S)=2m'(Cu₂S)/M(Cu₂S)n(Cu)
w=2*14.72/(159.16*0.2)=0.925 (92.5%)

You might be interested in
How much heat, in joules and in calories, must be added to a 75.0–g iron block with a specific heat of 0.449 j/g °c to increase
Marina CMI [18]
The amount of heat needed would be the specific heat multiplied by the mass of the substance and the temperature difference. In this case, the mass would be 75.0–g, the specific heat  would be 0.449 j/g °c, and the temperature difference would be <span>1535 -25= 1510

Then the calculation would be: </span>0.449 j/g °c * 75g * 1510°c = 50,849.25J

In calorie it would be: 50849.25J / 4.184J/cal= 12,153.26 calorie
3 0
3 years ago
Where would you be likely find a generator?
tresset_1 [31]

Answer:

In an electrical room in A factory.

Explanation:

4 0
3 years ago
How many atoms of hydrogen are in 210 g of hydrogen peroxide (h2o2)?
Flauer [41]
Molar mass:

1 \ mol \ H_2O_2 = 34.0147 \ g \  H_2O_2

Grams to moles:

(210 \ g \ H_2O_2) * ( \frac{1 \ mol \  H_2O_2 }{34.0147 \ g \ H_2O_2}) = 6.17 \ mol \ H_2O_2

Moles to atoms (Avogadro's number):
1 \ mol = 6.022 * 10^{22} \ particles
(6.17 \ mol \ H_2O_2) *  (\frac{6.022 * 10^{22} \ molecules \ H_2O_2}{1 \ mol \ H_2O_2}) * ( \frac{2 \ atoms \ H}{molecule \ H_2O_2})

Answer:
= 7.43 * 10^{23} \ H \ atoms
5 0
3 years ago
Read 2 more answers
Hi question, what number should I change the 9 to so it's balanced?
Delicious77 [7]

Answer:

3

Explanation:

6 0
3 years ago
Why will liquids evaporate even at room temperature?
mr Goodwill [35]
<h2>It can happen when liquids are cold or when they are warm. ... It turns out that all liquids can evaporate at room temperature and normal air pressure. Evaporation happens when atoms or molecules escape from the liquid and turn into a vapor. Not all of the molecules in a liquid have the same energy.</h2>
6 0
3 years ago
Other questions:
  • Thomsons experiments were significant in that they questioned
    6·1 answer
  • Which of the following are examples of physical properties
    12·1 answer
  • Which chemical equation represents a redox reaction? A. Mg(ClO3)2 + 2HCl → MgCl2 + 2HClO3 B. CO + H2O → H2 + CO2 C. 2NH4NO3 + Cu
    9·2 answers
  • A _______ change does not change the identity of the substance but a _______ change does.
    8·1 answer
  • Plsss help will give BRAINLIEST
    15·1 answer
  • How many moles are in 230 grams of NaCl?
    13·1 answer
  • Explain what is happening during a redox reaction.
    5·1 answer
  • The mass of all elements on the periodic table are based on which element?
    14·2 answers
  • Scientists are able to identify characteristics of the Earth's inner layers because of
    5·1 answer
  • Clo3− draw the molecule by placing atoms on the grid and connecting them with bonds. Include all lone pairs of electrons. Show t
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!