The chemical formula of one of the nitrogen oxides is N2O5. What mass of nitrogen would be found in 54 g of N2O5? Select one: 33 g 46 g 14 g 7g 28 g
The Correct Answer and Explanation is:
To determine the mass of nitrogen in 54 g of N2O5, we need to follow these steps:
Step 1: Find the molar mass of N2O5
The molar mass of N2O5 is calculated by adding the atomic masses of nitrogen (N) and oxygen (O) in the formula.
- Atomic mass of nitrogen (N) = 14.01 g/mol
- Atomic mass of oxygen (O) = 16.00 g/mol
The molar mass of N2O5 is:Molar mass of N2O5=2×14.01 g/mol (N)+5×16.00 g/mol (O)=28.02 g/mol+80.00 g/mol=108.02 g/mol\text{Molar mass of N2O5} = 2 \times 14.01 \, \text{g/mol (N)} + 5 \times 16.00 \, \text{g/mol (O)} = 28.02 \, \text{g/mol} + 80.00 \, \text{g/mol} = 108.02 \, \text{g/mol}Molar mass of N2O5=2×14.01g/mol (N)+5×16.00g/mol (O)=28.02g/mol+80.00g/mol=108.02g/mol
Step 2: Calculate the mass of nitrogen in N2O5
The formula N2O5 contains 2 nitrogen atoms. The mass of nitrogen in one mole of N2O5 is:Mass of nitrogen in N2O5=2×14.01 g=28.02 g\text{Mass of nitrogen in N2O5} = 2 \times 14.01 \, \text{g} = 28.02 \, \text{g}Mass of nitrogen in N2O5=2×14.01g=28.02g
So, in 108.02 g of N2O5, there is 28.02 g of nitrogen.
Step 3: Use the ratio to find the mass of nitrogen in 54 g of N2O5
Now, we use a proportion to find the mass of nitrogen in 54 g of N2O5:Mass of nitrogen in 54 g of N2O5Mass of nitrogen in 108.02 g of N2O5=54 g108.02 g\frac{\text{Mass of nitrogen in 54 g of N2O5}}{\text{Mass of nitrogen in 108.02 g of N2O5}} = \frac{54 \, \text{g}}{108.02 \, \text{g}} Mass of nitrogen in 108.02 g of N2O5Mass of nitrogen in 54 g of N2O5=108.02g54gMass of nitrogen in 54 g of N2O5=54 g108.02 g×28.02 g=14.01 g\text{Mass of nitrogen in 54 g of N2O5} = \frac{54 \, \text{g}}{108.02 \, \text{g}} \times 28.02 \, \text{g} = 14.01 \, \text{g}Mass of nitrogen in 54 g of N2O5=108.02g54g×28.02g=14.01g
Conclusion
The mass of nitrogen in 54 g of N2O5 is 14 g. Therefore, the correct answer is 14 g.
