How many moles of S2F10 are contained in a pure 128-gram sample of S2F10?

0.504 mole

Explanation:

From the question given, the mass of S2F10 = 128g

To obtain the number of mole in 128g of S2F10, we must obtain the molar mass of S2F10.

Molar Mass of S2F10 = (32x2) + (19x10) = 64 + 190 = 254g/mol.

Now, we can obtain the number of mole as follow:

Number of mole = Mass / Molar Mass

Number of mole of S2F10 = 128/254 = 0.504 mole