It is called convection. When warm air, or current, moves up and disperse outwards as cold air, or current, moves into the warmer region.
Answer:
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Explanation:
Here, we want to get the equation of the reaction between Hydrochloric acid and Zinc metal
Zinc metal displaces the hydrogen from hydrochloric acid to form zinc chloride
We have the equation of reaction as:
A is correct................
CF4 or Tetrafluoromethane is a ionic compound
As we know that
A<span>t STP
1 mole of any gas occupies 22.4L
so
15.7L / 22.4L/mole = 0.7moles Cl2
0.7moles x 6.022x10^23molecules/mole = 4.22x10^23molecules
hope it helps</span>