Elemental sulfur occurs as octatomic molecule S8. What is the mass of Fluorine gas needed to react completely with 19.9 g of Sulfur to form sulfur hexafluoride?
Relative atomic mass of F2 = 19
RAM of Sulphur = 32
Mass of fluorine required to form SF6
= 19.9*(6*19)/32
= 70.9 g
To find the mass of fluorine gas needed to react completely with 19.9 g of sulfur, we need to take into account the balanced chemical equation for the reaction between sulfur and fluorine to form sulfur hexafluoride.
The balanced chemical equation for the reaction is:
S8 + 24 F2 -> 8 SF6
From the equation, we can see that 1 mole of S8 reacts with 24 moles of F2 to produce 8 moles of SF6.
1. Calculate the molar mass of sulfur (S):
The molar mass of sulfur is the sum of the atomic masses of its constituent atoms, which is 32.06 g/mol.
2. Convert the mass of sulfur (19.9 g) to moles:
Using the formula:
moles = mass / molar mass
moles of S = 19.9 g / 32.06 g/mol ≈ 0.621 mol
3. Use stoichiometry to calculate the moles of fluorine gas needed:
According to the balanced equation, the ratio of moles between S8 and F2 is 1:24.
moles of F2 = moles of S8 * (24 moles F2 / 1 mole S8) ≈ 0.621 mol * 24 ≈ 14.9 mol
4. Convert the moles of fluorine gas to mass:
Using the formula:
mass = moles * molar mass
mass of F2 = 14.9 mol * molar mass of F2
The molar mass of fluorine (F2) is 38.00 g/mol (2 x 19.00 g/mol per fluorine atom).
mass of F2 = 14.9 mol * 38.00 g/mol ≈ 565 g
Therefore, approximately 565 grams of fluorine gas are needed to react completely with 19.9 g of sulfur to form sulfur hexafluoride (SF6).