Question

Elemental sulfur (1.256 g) is combined with fluorine, Fz' to give a compound with the formula SF, a very stable, colorless gas. If you have isolated 5.722 g of SF what is the value of x?

Select one:
a. 4
b. 1
c. 6
d. 2

Answer 1

To find the value of x in the SFx compound, we calculate the moles of sulfur and fluorine based on their masses and atomic masses.

Step-by-step explanation:

To determine the value of x in the compound SFx, we can use the atomic masses of sulfur (S) and fluorine (F). Since 1.256 g of elemental sulfur is used to produce 5.722 g of SFx, the mass of fluorine present in the compound is 5.722 g - 1.256 g = 4.466 g. The atomic mass of sulfur is approximately 32 g/mol and that of fluorine is approximately 19 g/mol. Therefore, the moles of sulfur in the compound are 1.256 g / 32 g/mol = 0.03925 mol. The moles of fluorine are 4.466 g / 19 g/mol = 0.235 mol.

Since the ratio of moles of fluorine to sulfur should be the same as the ratio of atoms in the compound (which is x), we can find x by dividing the moles of fluorine by the moles of sulfur: 0.235 mol / 0.03925 mol = 5.99. As x must be an integer, and we are dealing with standard stoichiometric compounds, we round this to 6. Therefore, x is 6, making the formula of the compound SF6. Dividing the moles of fluorine by that of sulfur gives a value close to 6, hence x equals 6, and the compound's formula is SF6.