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# CIE A-levels Chemistry watch

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1. Which would contain 9.03 × 1023 oxygen atoms?
A 0.25 mol aluminium oxide
B 0.75 mol sulfur dioxide
C 1.5 mol sulfur trioxide
D 3.0 mol water

I would really appreciate it if someone showed me how to do the working. The answer scheme says it's B.
2. In 0.75 mol of SO2 you would have 0.75 x 2=1.5 mol of oxygen, time that by the avogadro constant to get number of oxygen atoms 1.5 x (6.02 x 10^23) =9.03 x 10^23
3. (Original post by Rachoo1)
In 0.75 mol of SO2 you would have 0.75 x 2=1.5 mol of oxygen, time that by the avogadro constant to get number of oxygen atoms 1.5 x (6.02 x 10^23) =9.03 x 10^23
Thank you very much

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Updated: November 7, 2017
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