Question #b736b

1 Answer
Nov 26, 2014

We can solve this by making a table as follows:

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*Calculation of Mole Ratio: Divide the number in the previous cell by the lowest value in the previous column. In this case, the lowest value in the 4th column is 0.79, so every number should be divided by 0.79.

**Calculation of Whole Number Ratio: Round off the number obtained in the previous cell to the closest whole number.

Now that we have obtained the whole number ratios of the element, we can find the Empirical Formula. There are 5 atoms of fluorine for every atom of sulphur.

Empirical Formula: SF5

Now,

Molar mass of the compound = 254.1 g/mol

The molecular formula can be calculated by multiplying the empirical formula by the ratio n, given by:

n= Molar Mass / Empirical Formula Mass


Note: Empirical Formula Mass can be calculated using the Empirical Formula. In that, there is one sulphur atom and five fluorine atoms. Thus, the empirical formula mass

=1(Smass)+5(Fmass)
=1(32)+5(19)
=127


Therefore, n=254.1127
n=2 (approx.)

Molecular Formula = (Empirical Formula) × n
=SF5×2

=S2F10

Thus, the empirical formula of the compound is SF5 and the molecular formula is S2F10.


I hope I was able to help!