pyrite, FeS2 reactswhen it is heated strongly in the air according to the equation
4 FeS2(s) + 11 O2 rightarrow 2 Fe2O3(s) + 8 SO2(g)
What volume of sulfir dioxide ( measured at room temprature and pressure) would be produced by heating 100g of pyrite in excess of air
Molar volume ofgas at room temprature =24dm3
I don't understand how this is supposed to be sloved
To solve this problem, you need to use the concept of stoichiometry to determine the number of moles of sulfur dioxide produced, and then use the molar volume at room temperature to find the volume.
Let's break down the steps:
Step 1: Determine the number of moles of pyrite (FeS2)
To do this, we need to calculate the molar mass of FeS2:
Fe: atomic mass = 55.845 g/mol
S: atomic mass = 32.06 g/mol
Molar mass of FeS2 = (2 x atomic mass of Fe) + atomic mass of S
= (2 x 55.845 g/mol) + 32.06 g/mol
= 119.74 g/mol
Now, we can determine the number of moles of pyrite by dividing the given mass (100g) by the molar mass:
Number of moles of pyrite = Mass / Molar mass
= 100g / 119.74 g/mol
= 0.835 mol
Step 2: Determine the number of moles of sulfur dioxide (SO2)
From the balanced chemical equation, we can see that for every 4 moles of FeS2, 8 moles of SO2 are produced. Therefore, we can set up a proportion:
4 moles FeS2 : 8 moles SO2 = 0.835 mol FeS2 : x (moles of SO2)
Solving for x, we can find the number of moles of SO2 produced:
x = (8 moles SO2 * 0.835 mol FeS2) / (4 moles FeS2)
x = 1.67 mol SO2
Step 3: Convert moles of SO2 to volume at room temperature and pressure
We know that the molar volume of gas at room temperature is 24 dm^3/mol. Using this information, we can convert the number of moles of SO2 to volume:
Volume of SO2 = Number of moles * Molar volume
= 1.67 mol * 24 dm^3/mol
= 40.08 dm^3
Therefore, the volume of sulfur dioxide produced at room temperature and pressure from heating 100g of pyrite in excess air is 40.08 dm^3.
To solve this problem, we need to use stoichiometry and the molar mass of substances involved in the reaction. Here are the steps to find the volume of sulfur dioxide produced when 100g of pyrite is heated in excess air:
Step 1: Determine the number of moles of pyrite.
The molar mass of pyrite (FeS2) can be calculated as follows:
Fe: 55.845 g/mol
S: 32.06 g/mol
Multiply the molar mass of Fe by 2 and add it to the molar mass of S to get the molar mass of pyrite:
Molar mass of pyrite = (55.845 g/mol * 2) + 32.06 g/mol ≈ 119.76 g/mol
To find the number of moles, divide the given mass (100g) by the molar mass:
Number of moles of pyrite = 100g / 119.76 g/mol ≈ 0.8356 mol
Step 2: Determine the moles of sulfur dioxide produced.
From the balanced equation, we see that for every 4 moles of pyrite, 8 moles of sulfur dioxide (SO2) are produced. Therefore, we can set up a ratio:
4 moles of pyrite : 8 moles of sulfur dioxide
Since we have calculated the number of moles of pyrite as 0.8356 mol, we can apply this ratio to find the moles of sulfur dioxide:
0.8356 mol pyrite * (8 mol SO2 / 4 mol pyrite) = 1.6712 mol SO2
Step 3: Convert moles of sulfur dioxide to volume.
Using the molar volume at room temperature (24 dm^3/mol), we can convert the moles of sulfur dioxide to volume:
1.6712 mol SO2 * 24 dm^3/mol ≈ 40.1088 dm^3
Therefore, when 100g of pyrite is heated in excess air, it would produce approximately 40.1088 dm^3 (or 40.11 dm^3, rounded to two decimal places) of sulfur dioxide measured at room temperature and pressure.
You slove it this way.
mols FeS2 = grams/molar mass = ?
Using the coefficients in the balanced equation, convert mols FeS2 to mols SO2.
Now convert mols SO2 to volume.
mols SO2 x 24 dm3/mol = ? dm3.