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
Dimas [21]
3 years ago
10

Which is an example of a pure substance? A. coffee B. helium C. vinegar D. trail mix

Chemistry
1 answer:
bogdanovich [222]3 years ago
5 0

B. Helium

It has only He atoms

You might be interested in
PLEASE PEOPLE I NEED HELP PLEASE IF YOU SEE THIS HELP ME ! :,( !!!!! PLEASEEEEEEEEE
Tems11 [23]

Answer:

year 1 is 5.5%

year 2 is 7.5%

year 3 is 10.2%

Explanation:

since,

length of the transect covered in seaweed / total lenth of transect x 100

then,

0.55 / 10.0 x 100 = 5.5

and

0.75 / 10.0 x 100 = 7.5

and

1.02 / 10.0 x 100 = 10.2

you could also just move the decimal to the right once

:)

4 0
3 years ago
Which object represents a simple machine? A)battery B)pliers C)Match D)candle
Anna35 [415]
Battery represents a simple machine
6 0
3 years ago
Read 2 more answers
3.
sineoko [7]

Answer:

3. V = 0.2673 L

4. V = 2.4314 L

5. V = 0.262 L

6. V = 2.224 L

Explanation:

3. assuming ideal gas:

  • PV = RTn

∴ R = 0.082 atm.L/K.mol

∴ V1 = 225 L

∴ T1 = 175 K

∴ P1 = 150 KPa = 1.48038 atm

⇒ n = RT/PV

⇒ n = ((0.082 atm.L/K.mol)(175 K))/((1.48038 atm)(225 L))

⇒ n = 0.043 mol

∴ T2 = 112 K

∴ P2 = P1 = 150 KPa = 1.48038 atm

⇒ V2 = RT2n/P2

⇒ V2 = ((0.082 atm.L/K.mol)(112 K)(0.043 mol))/(1.48038 atm)

⇒ V2 = 0.2673 L

4. gas is heated at a constant pressure

∴ T1 = 180 K

∴ P = 1 atm

∴ V1 = 44.8 L

⇒ n = RT/PV

⇒ n = ((0.082 atm.L/K.mol)(180 K))/((1 atm)(44.8 L))

⇒ n = 0.3295 mol

∴ T2 = 90 K

⇒ V2 = RT2n/P

⇒ V2 = ((0.082 atm.L/K.mol)(90 K)(0.3295 mol))/(1 atm)

⇒ V2 = 2.4314 L

5.  V1 = 200 L

∴ P1 = 50 KPa = 0.4935 atm

∴ T1 = 271 K

⇒ n = RT/PV

⇒ n = ((0.082 atm.L/K.mol)(271 K))/((0.4935 atm)(200 L))

⇒ n = 0.2251 mol

∴ P2 = 100 Kpa = 0.9869 atm

∴ T2 = 14 K

⇒ V2 = RT2n/P2

⇒ V2 = ((0.082 atm.L/K.mol)(14 K)(0.2251 mol))/(0.9869 atm)

⇒ V2 = 0.262 L

6.a)  ∴ V1 = 24.6 L

∴ P1 = 10 atm

∴ T1 = 25°C = 298 K

⇒ n = RT/PV

⇒ n = ((0.082 atm.L/K.mol)(298 K))/((10 atm)(24.6 L))

⇒ n = 0.0993 mol

∴ T2 = 273 K

∴ P2 = 101.3 KPa = 0.9997 atm

⇒ V2 = RT2n/P2

⇒ V2 = ((0.082 atm.L/K.mol)(273 K)(0.0993 mol))/(0.9997 atm)

⇒ V2 = 2.224 L

3 0
3 years ago
8. Bring the balloon in contact with the wall. What happens to the charges in the wall?
Ne4ueva [31]

When the charged balloon is brought near the wall, it repels some of the negatively charged electrons in that part of the wall. Therefore, that part of the wall is left repelled.

<u>Explanation</u>:  

  • Balloons don't stick to walls. However, if you rub the balloon on an appropriate piece of material such as clothing or a wall, electrons are pulled from the other material to the balloon.
  • The balloon now as more electrons than normal and therefore has an overall negative charge. Two balloons like this will repel each other.
  • The other material now has an overall positive charge. Because opposite charges attract, the balloon will now appear to stick to the other material. If you didn't rub the balloon first, it's charge would be neutral and it wouldn't stick to the wall.
7 0
4 years ago
What particle is J.J Thomson credited with discovering
Ilya [14]
He was credited with discovering the subatomic particle also known as the electron in 1897.
6 0
3 years ago
Other questions:
  • If you multiply an objects weight times it height, what value do you compute?
    13·2 answers
  • Name four types of pathogens that could cause infectious disease??
    14·1 answer
  • The sodium chloride molecule breaks apart in water. what does a represent
    13·1 answer
  • How many grams of nitric acid are needed to produce 30.0 g of water?
    9·1 answer
  • A 0.1014 g sample of a purified CHO compound was burned in a combustion apparatus and produced 0.1486 g CO2 and 0.0609 g of H2O.
    14·1 answer
  • What other elements might you expect to have chemical properties similar to zinc❔
    5·1 answer
  • A glass breaks is a physical or chemical change
    10·2 answers
  • How many protons and neutrons are there in an atom of 3.K?
    7·1 answer
  • This woman comes to the clinic with high blood pressure,
    5·1 answer
  • Which example in the video is a physical change?
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!