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Calculate the number of Pt atoms in the cube and find the radius in picometers of a Pt atom. Be sure your answer has the correct number of significant digits. Full questions are in pictures...Thank you!

Calculate the number of Pt atoms in the cube and find the radius in picometers of-example-1
User Stalin
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1 Answer

13 votes
13 votes

V cube = 2.2³ = 10.648 cm³

V Pt atoms = 0.75(75%) x 10.648 = 7.986 cm³

Part 1

mass of a single Pt atom = 3.24 x 10⁻²² g

mass Pt atoms = ρ x V = 21.45 g/cm³ x 7.986 cm³ = 171.3 g

the number of Pt atoms = 171.3 : 3.24 x 10⁻²² = 5.287 x 10²³

Part 2

4/3πr³=7.986 cm³

r = 1.24 cm = 1.24 x 10¹⁰ pm

User Mehrdad Afshari
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