The percent composition by mass of oxygen in [tex]Ca(NO_3)_2[/tex] will be 58.54%
The percent composition by mass of a compound is mathematically given by:
Percent composition by mass = mass of component/total mass x 100
In this case, there are 6 atoms of oxygen in the compound.
6 x 16 = 96 g/mole
Percent composition by mass of oxygen = 96/164 x 100 = 58.54%
More on percentage composition can be found here: https://brainly.com/question/1350382
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