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
slava [35]
2 years ago
5

How many moles are there in 3.9 grams of potassium

Chemistry
1 answer:
polet [3.4K]2 years ago
3 0

Answer:0.025576559594663 mole.

Explanation:

You might be interested in
A small diamond, which is made of pure carbon, contains too many carbon atoms to count individually. Which is closest to the num
8090 [49]

The correct answer is option C, 5.02 x 10²² carbon atoms

Atomic mass of C = 12 g/mol

According to Avogadro, 1 mole of C has 6.023 x 10²³C atoms

Now 1 mole of C is equal to 12 g

Therefore, 12 g of C = 6.023 x 10²³ C atoms

1 g of C = \frac{6.023 x 10^2^3}{12} C atoms = 5.02 x 10²² C atoms

7 0
2 years ago
Through the complete electrolysis of a sample of pure water, a student collects 14.0 grams of hydrogen gas and 112.0 grams of ox
Vadim26 [7]

Answer:

126.0g of water were initially present

Explanation:

The electrolysis of water occurs as follows:

2H₂O(l) ⇄ 2H₂(g) + O₂(g)

<em>Where 2 moles of water produce 2 moles of hydrogen and 1 mole of oxygen.</em>

<em />

To find the mass of water we need to determine moles of oxygen and hydrogen, thus:

<em>Moles Hydrogen:</em>

14.0g H₂ ₓ (1mol / 2g H₂) = 7 moles H₂

<em>Moles Oxygen:</em>

112.0g O₂ ₓ (1mol / 32g) = 3.5 moles O₂

Based on the chemical equation, the moles of water initially present were 7 moles (That produce 7 moles H₂ and 3.5 moles O₂). The mass of 7 moles of H₂O is:

7 moles H₂O * (18g / mol) =

<h3>126.0g of water were initially present</h3>
6 0
3 years ago
Assume that a firm has the following marginal benefit of pollution (denoted E for emissions, measured in tons): MB=150-5 E e. No
jeka57 [31]

Answer:

Explanation:

E)cost of pollution is reduction in benefit of the firms.

MB=150-5E,. MB=90-3E

E=30-MB/5. E=30-MB/3

Joint MB,

E=60-8MB/15

MB=112.5-1.875E

Total pollution reduction=24

Total pollution=60-24=36

MB=112.5-1.875*36=112.5-67.5=45

Firm 1

MB=150-5E.

45=150-5E.

E=-105/-5=21

Reduction=30-21=9

Firm 2,

MB=90-3E

45=90-3E

E=-45/-3=15

Reduction =30-15=15

So firm 2 is reducing 15 units of pollution and firm 1 reducing 9 units of pollution.

As each firm have to reduce 12 units of pollution but firm 2 reducing 3 units more while firm 1 reducing 3 less units.

So, firm 2 is selling 3 units of pollution emission permit to firm 1.

F)firm 1 reduce 9 units and firm 2 reduce 12 units of pollution after trade.

Total cost of pollution reduction will total Benefit reduction by pollution reduction.

MB=112.5 -1.875E

TB=112.5E-0.9375E^2

TB at E=60

TB=112.5*60-0.9375*60*60=6750-3375=3375

TB at E=36

TB=112.5*36-0.9375*36*36=4050-1215=2836

Total cost of pollution reduction=3375-2836=540

G)price of permit= cost of extra pollution reduction by firm 2 or total cost from 9 to 12 by firm 2

MB=90-3E

TB=90E- 1.5E^2

TB at E=18

TB=90*18 -1.5*18*18=1620-486=1134

TB at E=15

TB=90*15 -1.5*15*15=1350-337.5=1012.5

Permit price=1134-1012.5=121.5

Total cost to firm 2 =1134

Net total cost to firm 2=1134-121.5=1012.5

Total cost to firm 1=150E-2.5E^2=150*9-2.5*9*9=1350-202.5=1147.5

Net total cost=1147.5+121.5=1269

H) the total cost is lower in cap & trade policy is because the firm who has higher cost of pollution reduction is paying the other firm who has lower cost of pollution reduction to reduce more pollution ,so that his part of pollution reduction can be completed.

And the amount he is paying is equal to the amount that is cost of other firm of reducing additional pollution units.

So the cost the firm is lower as he is paying lower amount than if he reduce pollution by itself.

5 0
3 years ago
Help!!!<br> (I'll only give brainliest if it's right)
vivado [14]

Answer:

flavio because you need a source of energy in order for it to have energy

Explanation:

can i have brainliest so i can rank up

5 0
3 years ago
Read 2 more answers
Over-encouraging lesser skilled players can lead to embarrassment.<br> a. True<br> b. False
Margarita [4]
My answer would be a. True
6 0
3 years ago
Read 2 more answers
Other questions:
  • Please help both these answers use the graph . I will mark brainly !!
    5·1 answer
  • Are blue stars young or old? How can you tell?.
    7·1 answer
  • All the molecules of a substance possess the "average kinetic energy" value.
    12·1 answer
  • Describe what is happening to the density of the aqueos solution as salt is being added​
    8·2 answers
  • Which type of particle retains the identity of an element during a chemical reaction? a) electron
    13·1 answer
  • How much heat is required to raise the temperature of 88.5 g of water from its melting point to its boiling point?
    10·1 answer
  • What describes an impermeable rock where oil and natural gas deposits are found ?
    9·1 answer
  • Name the process which takes place when
    10·2 answers
  • Help ill give brainliest need help with number 8
    5·2 answers
  • Entir<br> What is the striking back of<br> the<br> bunsen-<br> burner?
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!