Question

calculate the percent oxygen in potassium chlorate

Answer 1

To calculate the percent oxygen in potassium chlorate (KClO₃), you first need the molar masses of each component in the compound:

- Potassium (K): approximately 39.10 g/mol
- Chlorine (Cl): approximately 35.45 g/mol
- Oxygen (O): approximately 16.00 g/mol

Now, we can calculate the molar mass of potassium chlorate (KClO₃):

\[
\text{Molar mass of KClO₃} = (\text{Molar mass of K}) + (\text{Molar mass of Cl}) + 3 \times (\text{Molar mass of O})
\]

\[
\text{Molar mass of KClO₃} = 39.10 \, \text{g/mol} + 35.45 \, \text{g/mol} + 3 \times 16.00 \, \text{g/mol}
\]

\[
\text{Molar mass of KClO₃} = 39.10 + 35.45 + 48.00
\]

\[
\text{Molar mass of KClO₃} = 122.55 \, \text{g/mol}
\]

Next, to find the total mass of oxygen in one mole of potassium chlorate:

\[
\text{Mass of O in KClO₃} = 3 \times 16.00 \, \text{g/mol} = 48.00 \, \text{g/mol}
\]

Now, calculate the percent composition of oxygen in potassium chlorate:

\[
\text{Percent oxygen} = \left( \frac{\text{Mass of O}}{\text{Molar mass of KClO₃}} \right) \times 100
\]

\[
\text{Percent oxygen} = \left( \frac{48.00 \, \text{g/mol}}{122.55 \, \text{g/mol}} \right) \times 100
\]

\[
\text{Percent oxygen} \approx 39.1\%
\]

Thus, the percent oxygen in potassium chlorate is approximately **39.1%**.