The molecular formula of disulfur dioxide is S2O2. What is the empirical formula of disulfur dioxide?
Question 2
In Lab #7, you collected these values:
mass of crucible = 21.3456 g
mass of crucible plus copper wire = 21.4409 g
mass of crucible plus copper sulfide = 21.4649 g
Calculate the moles of copper (round your answer to five decimal places).
0.00150
0.01550
0.00220
0.00110
The Correct Answer and Explanation is :
Question 1: Empirical Formula of Disulfur Dioxide
Disulfur dioxide has the molecular formula S2O2. To find its empirical formula, we need to determine the simplest whole number ratio of atoms in the compound.
- Step 1: Identify the subscripts in the molecular formula.
- The molecular formula is S2O2. This indicates 2 sulfur atoms (S) and 2 oxygen atoms (O).
- Step 2: Simplify the ratio of atoms.
- Both sulfur and oxygen are present in a ratio of 2:2. We can simplify this ratio by dividing both numbers by their greatest common divisor, which is 2.
- Step 3: Simplify the formula.
- Dividing both the subscripts (2 for sulfur and 2 for oxygen) by 2 results in S1O1, which simplifies to SO.
Therefore, the empirical formula of disulfur dioxide is SO.
Question 2: Moles of Copper in Lab #7
We are given the following data from Lab #7:
- Mass of crucible = 21.3456 g
- Mass of crucible plus copper wire = 21.4409 g
- Mass of crucible plus copper sulfide = 21.4649 g
Step 1: Calculate the mass of copper wire.
To find the mass of the copper wire, we subtract the mass of the crucible from the mass of the crucible plus copper wire:
[
\text{Mass of copper wire} = 21.4409 \, \text{g} – 21.3456 \, \text{g} = 0.0953 \, \text{g}
]
Step 2: Calculate the mass of copper sulfide.
Next, subtract the mass of the crucible from the mass of the crucible plus copper sulfide:
[
\text{Mass of copper sulfide} = 21.4649 \, \text{g} – 21.3456 \, \text{g} = 0.1193 \, \text{g}
]
Step 3: Calculate the mass of sulfur in copper sulfide.
The mass of sulfur is the difference between the mass of copper sulfide and the mass of copper wire:
[
\text{Mass of sulfur} = 0.1193 \, \text{g} – 0.0953 \, \text{g} = 0.0240 \, \text{g}
]
Step 4: Calculate the moles of copper.
To calculate the moles of copper, we use the molar mass of copper, which is 63.55 g/mol. The number of moles of copper is given by the formula:
[
\text{Moles of copper} = \frac{\text{Mass of copper}}{\text{Molar mass of copper}}
]
Substitute the values:
[
\text{Moles of copper} = \frac{0.0953 \, \text{g}}{63.55 \, \text{g/mol}} = 0.00150 \, \text{mol}
]
So, the correct answer is 0.00150.
Conclusion:
- The empirical formula of disulfur dioxide is SO.
- The number of moles of copper is 0.00150 mol.
This answer is determined by careful calculation using the given mass data and the molar mass of copper. The result reflects the correct amount of copper used in the reaction.