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shtirl [24]
3 years ago
12

How many atoms are there in 90.2 grams of selenium?

Chemistry
1 answer:
Neko [114]3 years ago
4 0
First calculate the moles of selenium by multiplying the mass x molar mass
90.2 × 78.96 = 7122.2 moles

Number of moles multiplied by avogadros number gives number of atoms
7122.2 × 6.022 × 10^{23} = 4.289×10^{27} atoms
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Answer:

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