Molar mass:
Atomic mass O = 16.0 a.m.u
O₃ = 16.0 x 3 => 48.0 g/mol
Therefore:
1 mole O₃ --------------- 48.0 g
0.020 mole O₃ ---------- ??
0.020 x 48.0 / 1 =
0.96 / 1 => 0.96 g
hope this helps!
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