I believe the answer is D
Answer:
Pb: 22.4 at%
Sn: 77.6 at%
Explanation:
It is possible to find at% of Pb and Sn converting mass in moles using molar mass assuming a basis of 100g, thus:
Pb: 33.5g × (1mol / 207.2g) = <em>0.1617mol</em>
Sn: 66.5g × (1mol / 118.7g) = <em>0.5602mol</em>
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Total moles: 0.1617mol + 0.5602mol = 0.7219mol
Composition in at%:
Pb: 0.1617mol / 0.7219mol × 100 = <em>22.4 at%</em>
Sn: 0.5602mol / 0.7219mol × 100 = <em>77.6 at%</em>
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I hope it helps!
Answer:
where are the statements??
Explanation:
As we know that there are avogadro no. of atoms in 9 g of beryllium.
1 mole of beryllium = 6.02 * 10^23 atoms
so 2.5 mole= 6.02*10^23*2.5 i.e = <span>15.055 × 10^23 atoms </span>