The percent by mass of hydrogen in a compound that contains 2.45 g of hydrogen and 18.20 g of carbon is:

Total mass of the compound:=18.20+2.45

=20.65

Percentage by mass of hydrogen:=2.45÷20.65×100

=11.86%

Explanation:

Just follow the steps i have provided above

the ozone layer acts as a filter for the shorter wavelength and highly hazardous ultraviolet radiation (uvr) from the sun, protecting life on earth from its potentially harmful effects. when the sky is clear, there is an inverse relationship between stratospheric ozone and solar uvr measured at the earth's surface.

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