Certain refrigerants such as cfcs and hcfcs, when allowed to escape into the atmosphere, will

The answer is ; deplete the stratosphere ozone layer and allow harmful ultraviolet radiation from the sun to reach the earth.

CFCs and HCFCs decompose over years to release CL- radical. When these radicals reach the atmosphere, they react with ozone as shown in the equations below. They reduce the ozone to oxygen hence depleting the protective layer.

Cl(g) + 03(g) ClO(g) + 02(g) (1)

ClO(g) + O(g) Cl(g) + 02(g) (2)

a- all cells come from pre-existing cells

all matter is made up of atoms

in any element all atoms are the same

elements in a compound are always in a constant ratio: apex