Number of atoms in a compound formula: Be(C2H3O2)2. The answers provided are 4, 8, 15, 22 and 29. However, I think it should be 18 (7 inside the brackets +2 outside the brackets X 2). Can you tell me if any of the answers provided are correct and if so, why?

Number of atoms in a compound formula: Be(C2H3O2)2. The answers provided are 4, 8, 15, 22 and 29. However, I think it should be 18 (7 inside the brackets +2 outside the brackets X 2). Can you tell me if any of the answers provided are correct and if so, why?

It sounds to me like the answer should be 15, because (C₂H₃O₂)2 is 14 total atoms, since you add the subscripts then multiply by the coefficient. Because beryllium isn't in the bracket you don't multiply that by two, and add it at the end and get 15.

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