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
NeX [460]
2 years ago
6

How does air above a heated surface move?

Chemistry
1 answer:
anzhelika [568]2 years ago
6 0
<span> When air is warmed up, its molecules move faster and faster and as a result they move further from each other. They still have the same mass, but they now occupy a larger volume. This means that its density is smaller.
The opposite when air is cooled off. The molecules slow down, get closer together, occupy a smaller volume and therefore its density is bigger.

When air is warmed up, it goes up. Once it's up there, is cools off and goes back down. Near the heated surface the air gets warmed up again, goes up, cools down, goes back down, and again and again.
that is called convection cells
</span>
You might be interested in
What greek letter are used in the precise definition of a limit?
Ivan
Epsilon-delta would be the green letter that is used in the precision definition of a limit. (ε, δ).
5 0
3 years ago
How many moles of KOH are required to produce 4.79 g K3PO4 according to the following reaction? 3KOH + H3PO4 -----&gt; K3PO4 + 3
8_murik_8 [283]

Answer:

0.677 moles

Explanation:

Take the atomic mass of K = 39.1, O =16.0, P = 31.0

no. of moles = mass / molar mass

no. of moles of K3PO4 used = 4.79 / (39.1x3 + 31 + 16x4)

= 0.02256 mol

From the equation, the mole ratio of KOH : K3PO4 = 3 :1,

meaning every 3 moles of KOH used, produces 1 mole of K3PO4.

So, using this ratio, let the no. of moles of KOH required to be y.

\frac{3}{1} =\frac{y}{0.02256} \\

y = 0.02256 x3

y = 0.0677 mol

If you don't find exactly 0.677 moles as one of the options, go for the closest one. A very slight error may occur because of taking different significant figures of atomic masses when calculating.

5 0
3 years ago
How many mL of a stock 50% (w/v) KNO3 solution are needed to prepare 250 mL of a 20% (w/v) KNO3 solution?
Andre45 [30]

Answer:

100ml of a stock 50% KNO3 solutions are needed to prepare 250ml of a 20% KNO3 solution.

Explanation:

In the given question it is mentioned that

     S1=50%

      V2=250ml

      S2= 20%

We all know that

                     V1S1=V2S2

                     ∴V1=  V2×S2÷S1

                     ∴V1=  V2S2×1/S1

                      ∴V1= 250×20÷50

                       ∴V1= 100ml

 

6 0
3 years ago
You place 12.0 milliliters of water in a graduated cylinder. Then you add 15.0 grams of metal to the water and the new water lev
Marrrta [24]

Answer:

<h3>The answer is 7.85 g/mL</h3>

Explanation:

The density of a substance can be found by using the formula

density =  \frac{mass}{volume}  \\

volume = final volume of water - initial volume of water

volume = 13.91 - 12 = 1.91 mL

We have

density =  \frac{15}{1.91}  \\  = 7.853403141...

We have the final answer as

<h3>7.85 g/mL</h3>

Hope this helps you

8 0
3 years ago
Read 2 more answers
True or False? Nitrogen can get back into the atmosphere when dead plants and animals are decomposed by bacteria. The bacteria b
Readme [11.4K]

Answer: True

Explanation:

6 0
3 years ago
Read 2 more answers
Other questions:
  • This form of matter does not have definite shape and is not easily compressed.
    13·1 answer
  • Which of the following statements correctly describes the substance with the formula ki?
    7·2 answers
  • A gas exerts a pressure of 1.8 atm at a temperature of 60 degrees celsius. What is the new temperature when the pressure of the
    10·1 answer
  • The compound KOH is called
    14·2 answers
  • What type of variable should there only be one of in an experiment? A) dependent B) independent C) control D) responding​
    8·1 answer
  • How many grams of nacl are present in 11.00 moles?
    8·1 answer
  • Balance Cr2O3+Mg --&gt;Cr + MgO
    8·1 answer
  • 100 POINTS AND BRAINLIEST
    6·2 answers
  • Why is acylation reagent important.
    7·1 answer
  • When do you use the roman numerals when naming ionic compounds
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!