First, let\'s find out what we need. The question asks for the empirical formula of some compound. To do this, we are going to need to find the amount of moles of each substance. To find the moles of Sb, all we will need to do is divide the mass of Sb by the molar mass of Sb. To find the moles of S will be a bit more complicated. Since we know that Sulfur is left over after the reaction, we know that sulfur is in excess (meaning Sb is the only thing that will limit our reaction). Assuming this is an ideal gas, we can take the original amount of moles of Sulfur and subtract it from the moles we get later (after it is transferred to the other container). This will give us the amount of moles of Sulfur that reacted with the moles of Sb. So this is what we need: moles Sb = ? moles S (reacted with Sb) = ? Calculate moles Sb. moles Sb = (mass Sb) / (molar mass Sb) = (0.350g) / (121.76g/mol) = 2.87 x 10^-3 moles Calculate moles S. For this, we are going to have to use the PV = nRT equation two times. One for the S that is placed with the Sb, and one for the S that is placed in the container after the reaction. Moles of S BEFORE reaction: PV = nRT (10.72 atm)(0.100L) = n(0.082)(373.15 K) n = (10.72 atm)(0.100L) / (0.082)(373.15 K) = 0.035 moles S Moles of S AFTER reaction: PV = nRT (14.8 atm)(0.050L) = n(0.082)(323.15 K) n = (14.8 atm)(0.050L) / (0.082)(323.15 K) = 0.028 moles S Calculate moles of S that reacted with the Sb: Since the moles of S went down after the reaction, we know that the moles of S lost must have reacted with the Sb. So, we can simply find the change in moles of S to find the amount of S that reacted with the Sb. Moles of S before reaction - Moles of S after reaction = Moles of S reacted 0.035 moles S - 0.028 moles S = 7.07 x 10^-3 moles S Now that we have our moles of each element that reacted, we can find the empirical formula. To do this, we need to divide through by the element with the least amount of moles. So, in this case, we must divide through by the moles of Sb. (2.87 x 10^-3 moles Sb) / (2.87 x 10^-3 moles Sb) = 1 (7.07 x 10^-3 moles S) / (2.87 x 10^-3 moles Sb) = 2.46 = 2.5 We need subscripts that are integers in empirical formulas. To make 2.5 an integer, we can simply multiply it by 2 to make it 5. When we do this, we also need to multiply 1 by 2. 2.5 x 2 = 5 1 x 2 = 2 These numbers represent the subscripts for each of our elements in our compound. So the empirical formula would be: Sb2S5 Solution First, let\'s find out what we need. The question asks for the empirical formula of some compound. To do this, we are going to need to find the amount of moles of each substance. To find the moles of Sb, all we will need to do is divide the mass of Sb by the molar mass of Sb. To find the moles of S will be a bit more complicated. Since we know that Sulfur is left over after the reaction, we know that sulfur is in excess (meaning Sb is the only thing that will limit our reaction). Assuming this is an ideal gas, we can take.

1. First, let's find out what we need.
The question asks for the empirical formula of some compound. To do this, we are going to need
to find the amount of moles of each substance.
To find the moles of Sb, all we will need to do is divide the mass of Sb by the molar mass of Sb.
To find the moles of S will be a bit more complicated. Since we know that Sulfur is left over
after the reaction, we know that sulfur is in excess (meaning Sb is the only thing that will limit
our reaction). Assuming this is an ideal gas, we can take the original amount of moles of Sulfur
and subtract it from the moles we get later (after it is transferred to the other container). This will
give us the amount of moles of Sulfur that reacted with the moles of Sb.
So this is what we need:
moles Sb = ?
moles S (reacted with Sb) = ?
Calculate moles Sb.
moles Sb = (mass Sb) / (molar mass Sb) = (0.350g) / (121.76g/mol) = 2.87 x 10^-3 moles
Calculate moles S.
For this, we are going to have to use the PV = nRT equation two times. One for the S that is
placed with the Sb, and one for the S that is placed in the container after the reaction.
Moles of S BEFORE reaction:
PV = nRT
(10.72 atm)(0.100L) = n(0.082)(373.15 K)
n = (10.72 atm)(0.100L) / (0.082)(373.15 K) = 0.035 moles S
Moles of S AFTER reaction:
PV = nRT
(14.8 atm)(0.050L) = n(0.082)(323.15 K)
n = (14.8 atm)(0.050L) / (0.082)(323.15 K) = 0.028 moles S
Calculate moles of S that reacted with the Sb:
Since the moles of S went down after the reaction, we know that the moles of S lost must have
reacted with the Sb. So, we can simply find the change in moles of S to find the amount of S that
reacted with the Sb.
Moles of S before reaction - Moles of S after reaction = Moles of S reacted
0.035 moles S - 0.028 moles S = 7.07 x 10^-3 moles S

2. Now that we have our moles of each element that reacted, we can find the empirical formula.
To do this, we need to divide through by the element with the least amount of moles. So, in this
case, we must divide through by the moles of Sb.
(2.87 x 10^-3 moles Sb) / (2.87 x 10^-3 moles Sb) = 1
(7.07 x 10^-3 moles S) / (2.87 x 10^-3 moles Sb) = 2.46 = 2.5
We need subscripts that are integers in empirical formulas. To make 2.5 an integer, we can
simply multiply it by 2 to make it 5. When we do this, we also need to multiply 1 by 2.
2.5 x 2 = 5
1 x 2 = 2
These numbers represent the subscripts for each of our elements in our compound.
So the empirical formula would be:
Sb2S5
Solution
First, let's find out what we need.
The question asks for the empirical formula of some compound. To do this, we are going to need
to find the amount of moles of each substance.
To find the moles of Sb, all we will need to do is divide the mass of Sb by the molar mass of Sb.
To find the moles of S will be a bit more complicated. Since we know that Sulfur is left over
after the reaction, we know that sulfur is in excess (meaning Sb is the only thing that will limit
our reaction). Assuming this is an ideal gas, we can take the original amount of moles of Sulfur
and subtract it from the moles we get later (after it is transferred to the other container). This will
give us the amount of moles of Sulfur that reacted with the moles of Sb.
So this is what we need:
moles Sb = ?
moles S (reacted with Sb) = ?
Calculate moles Sb.
moles Sb = (mass Sb) / (molar mass Sb) = (0.350g) / (121.76g/mol) = 2.87 x 10^-3 moles
Calculate moles S.
For this, we are going to have to use the PV = nRT equation two times. One for the S that is
placed with the Sb, and one for the S that is placed in the container after the reaction.
Moles of S BEFORE reaction:

3. PV = nRT
(10.72 atm)(0.100L) = n(0.082)(373.15 K)
n = (10.72 atm)(0.100L) / (0.082)(373.15 K) = 0.035 moles S
Moles of S AFTER reaction:
PV = nRT
(14.8 atm)(0.050L) = n(0.082)(323.15 K)
n = (14.8 atm)(0.050L) / (0.082)(323.15 K) = 0.028 moles S
Calculate moles of S that reacted with the Sb:
Since the moles of S went down after the reaction, we know that the moles of S lost must have
reacted with the Sb. So, we can simply find the change in moles of S to find the amount of S that
reacted with the Sb.
Moles of S before reaction - Moles of S after reaction = Moles of S reacted
0.035 moles S - 0.028 moles S = 7.07 x 10^-3 moles S
Now that we have our moles of each element that reacted, we can find the empirical formula.
To do this, we need to divide through by the element with the least amount of moles. So, in this
case, we must divide through by the moles of Sb.
(2.87 x 10^-3 moles Sb) / (2.87 x 10^-3 moles Sb) = 1
(7.07 x 10^-3 moles S) / (2.87 x 10^-3 moles Sb) = 2.46 = 2.5
We need subscripts that are integers in empirical formulas. To make 2.5 an integer, we can
simply multiply it by 2 to make it 5. When we do this, we also need to multiply 1 by 2.
2.5 x 2 = 5
1 x 2 = 2
These numbers represent the subscripts for each of our elements in our compound.
So the empirical formula would be:
Sb2S5