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
jasenka [17]
3 years ago
12

Which of the following describes a perpetual-motion machine?

Chemistry
2 answers:
makkiz [27]3 years ago
5 0

Answer:

a motor that requires no energy input once it is running

Mashutka [201]3 years ago
4 0

Answer:

c

Explanation:

a p e x :)

You might be interested in
Where the oxygen comes from the air (21% O2 and 79% N2). If oxygen is fed from air in excess of the stoichiometric amount requir
guajiro [1.7K]

Answer:

y_{O2} =4.3%

Explanation:

The ethanol combustion reaction is:

C_{2}H_{5} OH+3O_{2}→2CO_{2}+3H_{2}O

If we had the amount (x moles) of ethanol, we would calculate the oxygen moles required:

x*1.10(excess)*\frac{3 O_{2}moles }{etOHmole}

Dividing the previous equation by x:

1.10(excess)*\frac{3 O_{2}moles}{etOHmole}=3.30\frac{O_{2}moles}{etOHmole}

We would need 3.30 oxygen moles per ethanol mole.

Then we apply the composition relation between O2 and N2 in the feed air:

3.30(O_{2} moles)*\frac{0.79(N_{2} moles)}{0.21(O_{2} moles)}=121.414 (N_{2} moles )

Then calculate the oxygen moles number leaving the reactor, considering that 0.85 ethanol moles react and the stoichiometry of the reaction:

3.30(O_{2} moles)-0.85(etOHmoles)*\frac{3(O_{2} moles)}{1(etOHmoles)} =0.75O_{2} moles

Calculate the number of moles of CO2 and water considering the same:

0.85(etOHmoles)*\frac{3(H_{2}Omoles)}{1(etOHmoles)}=2.55(H_{2}Omoles)

0.85(etOHmoles)*\frac{2(CO_{2}moles)}{1(etOHmoles)}=1.7(CO_{2}moles)

The total number of moles at the reactor output would be:

N=1.7(CO2)+12.414(N2)+2.55(H2O)+0.75(O2)\\ N=17.414(Dry-air-moles)

So, the oxygen mole fraction would be:

y_{O_{2}}=\frac{0.75}{17.414}=0.0430=4.3%

6 0
3 years ago
Elements in which the d-sublevel is being filled have the properties of
Nadya [2.5K]

Answer:

Elements in which the d-sublevel is being filled have the properties of metals

4 0
2 years ago
Read 2 more answers
What observations can you make about this group of people? Name one inference you can make from your observations.​
Stells [14]

Answer:

no no no who are these some look good but are black what is this

7 0
3 years ago
Read 2 more answers
What is the barycenter of the moon and the earth​
kirill [66]

Answer:

The barycenter is the point in space around which two objects orbit. For the Moon and Earth, that point is about 1000 miles (1700 km) beneath your feet, or about three-quarters of the way from the Earth's center to its surface.

Explanation:

6 0
3 years ago
How are breathing and cellular respiration related? (15 points if answered)
IgorLugansk [536]

Cellular respiration is not the same thing as breathing, but they are closely related. When you breathe in, you take in the When you breathe in, you take in the oxygen your cells need for cellular respiration. When you breathe out, you get rid of the carbon dioxide that your cells produce during cellular respiration

(hope this helps ^^)

7 0
2 years ago
Read 2 more answers
Other questions:
  • Earthquakes cause other natural disasters, such as the disaster in this photo from a major earthquake that hit Alaska in 1964. W
    7·1 answer
  • A certain weak acid, ha, has a ka value of 3.6×10−7. part a calculate the percent ionization of ha in a 0.10 m solution. express
    9·1 answer
  • Which element is in the same period as chlorine (Cl) ?
    8·1 answer
  • Conversion .5 km to inches
    8·2 answers
  • Which of the following correctly identifies a bryophyte
    6·1 answer
  • A water treatment tablet contains 20.0 mg of tetraglycine hydroperiodide, 40.0% of which is available as soluble iodine. If two
    11·1 answer
  • What is the role of carbon dioxide in photosynthesis
    8·1 answer
  • H2SO4 is a strong acid, but HSO4- is a weak acid
    8·2 answers
  • What is the difference between a mixture, a solution, and a pure substance?
    5·2 answers
  • What's the boiling point of water at 0 atmospheric pressure?
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!