8. If x grams of S are needed to obtain 0.4 grams of SO3, how many grams of SO2 can be obtained from the same amount of S?
(A) 0.32 g
(B) 0.62 g
(C) 0.40 g
(D) 0.16 g
(E) Can not be calculated from the given data.
I am not sure how to set up this problem. I calculate the molecular mass of S03 is 80.00 g, but what do I do next?
Compare SO3 and SO2.
the masses are in the ratio of (S+2O)/(S+3O)
multiply that by 40g
I get about 64/80 * 40
The chemical equation for the first reaction will be: 2S + 3O2 -> 2SO3
(.4gSO3)(1molSO3/80gSO3)=.005molSO3
Since there are 2moles of SO3 produced for every 2 moles of S, it is assumed that .005mol of S is used in the reaction to produce .4g of SO3.
To get the mass of SO2 produced using the same amount of S as of the first reaction, which is .005mol, we calculate:
(.005molS)(1molSO2/1molS)(64gSO2/1molSO2)= .32gSO2
The answer is A.
To solve this problem, you need to use the molar ratios between S and SO3 and between S and SO2.
First, calculate the molar mass of SO3:
Molar mass of SO3 = (molar mass of S) + (3 x molar mass of O)
= (32.06 g/mol) + (3 x 16.00 g/mol)
= 80.06 g/mol
Then, use the molar ratio between S and SO3 to find the number of moles of S required to obtain 0.4 grams of SO3:
Number of moles of SO3 = Mass of SO3 / Molar mass of SO3
= 0.4 g / 80.06 g/mol
= 0.004997 mol
Since the molar ratio between S and SO3 is 1:1, the number of moles of S needed is equal to the number of moles of SO3.
Now, to find the mass of SO2 that can be obtained from the same amount of S, we need to use the molar ratio between S and SO2.
The molar mass of SO2 is:
Molar mass of SO2 = (molar mass of S) + (2 x molar mass of O)
= (32.06 g/mol) + (2 x 16.00 g/mol)
= 64.06 g/mol
Since the molar ratio between S and SO2 is also 1:1, the number of moles of SO2 that can be obtained is also 0.004997 mol.
Finally, calculate the mass of SO2:
Mass of SO2 = Number of moles of SO2 x Molar mass of SO2
= 0.004997 mol x 64.06 g/mol
= 0.319 g
Therefore, the answer is approximately 0.32 g. So, the correct option is (A) 0.32 g.