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4 years ago

Why does hot air rise and cold air sink??

Chemistry

2 answers:

Ray Of Light [21]4 years ago

7 0

Explanation:

In hot air, molecules have more kinetic energy and due to this they move from one place to another. As a result, there occurs more number of collisions between the molecules. Due to this molecules of hot air tend to rise.

Whereas when air is cold then its molecules are closer to each other. As a result, they do not have enough kinetic energy and they do not move from their initial position.

Hence, cold air sinks because of lack of movement in its molecules.

DaniilM [7]4 years ago

3 0

<span>Hot air rises because the molecules are further apart so it can take more room. </span>Which makes hot air lighter than cold air. Cold air sinks because it has more molecules but in the same amount of room.

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4 years ago

Calculate the molarity of sodium chloride in a half-normal saline solution (0.45% NaCl). The molar mass of NaCl

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Answer:

0.077 M

Explanation:

Molarity is the representation of the solution.

Molarity:

It is amount of solute in moles per liter of solution and represented by M

Formula used for Molarity

M = moles of solute / Liter of solution . . . . . . . . . . (1)

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