Elemental S reacts with O2 to form SO3 according to the reaction:

Question

2S+3O2→2SO3

How many O2 molecules are needed to react with 5.27 g of S?
Express your answer numerically in units of molecules.
=????molecules

Part B
What is the theoretical yield of SO3 produced by 5.27 g of S?
Express your answer numerically in grams.
= ???g

Subtitle: Limiting reactant
Next, consider a situation in which all of the S is consumed before all of the O2 reacts, or one in which you have excess S because all of the O2 has been used up.
For each of the given situations, indicate whether S or O2 is the limiting reactant.
A) 3.0 mol Sulfur & 5.0mol oxygen
B)3.0 mol sulfur & 4.0 mol oxygen
C) 3.0 mol sulfur & 3.0 mol oxygen

Answer 1

Elemental S reacts with O2 to form SO3 according to the reaction:
2S+3O2→2SO3

How many O2 molecules are needed to react with 5.27 g of S?
Express your answer numerically in units of molecules.
=????molecules
mols S = g/atomic mass = 5.27/32 = 0.165
Convert to mols O2. That's 0.165 mols S x (3 mols O2/2 mols S) = 0.247
Convert to molecules O2 knowing that there are 6.02E23 molecules in 1 mol.

Part B
What is the theoretical yield of SO3 produced by 5.27 g of S?
Express your answer numerically in grams.
= ???g
From part A you know there are0.165 mols S. Looking at the equation, you get 1 mol SO3 for each mol S; therefore, you will get 0165 mol SO3. Convert to grams. grams = mols x molar mass = ?

Subtitle: Limiting reactant
Next, consider a situation in which all of the S is consumed before all of the O2 reacts, or one in which you have excess S because all of the O2 has been used up.
For each of the given situations, indicate whether S or O2 is the limiting reactant.
A) 3.0 mol Sulfur & 5.0mol oxygen
I do these the long way. Convert EACH to mols SO3 formed.
For S: 3.0 mols S x (2 mol SO3/2 mols S) = 3 mols SO3
For O: 5.0 mols O2 x (2 mols SO3/3 mols S) = 3.33 mols SO3.
You can form ONLY the smallest mols SO3; therefore, S is the limiting reagent (LR) and O2 will be the excess reagent (ER). The last two are done the same way.
Be sure to confirm all of the calculations AND make sure the numbers are rounded to the correct number of significant figures. I didn't check any of that.

B)3.0 mol sulfur & 4.0 mol oxygen
C) 3.0 mol sulfur & 3.0 mol oxygen

Answer 2

So for Part A it would be 1.48694^23?
Part B 13.21g?
I want to double check to get them right

Part C I was able to get them right, thank you so much.

Answer 3

In the equation S(s) + O2 (g)-----} 2SO2 (g). How many oxygen atoms are in the product 2SO2 (g)?