Verified Answer :

Number of moles = Mass/Formula Mass

Fm = 48(Four Carbons) + 152(8 Flourines)
Fm = 200

Number of Moles = 256/200

The number of moles in C4F8 is 1.28

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Answer:

1.325 moles of \(C_{4}F_{8}\) are in 265 g of \(C_{4}F_{8}\)

Explanation:

Number of moles of a compound=(mass of the compound)/(molar mass of the compound)

Molar mass of \(C_{4}F_{8}\) = \((4\times atomic mass of C)+(8\times atomic mass of F)\) or \((4\times 12g)+(8\times 19g)\) or 200 g.

So number of moles of \(C_{4}F_{8}\) in 265 g of \(C_{4}F_{8}\) is (265g/200g) or 1.325 moles