A pyrotechnician mixes 280 g of black powder for a firework. Find the amount of oxygen, carbon dioxide, and sulfur dioxide generated when this firework bursts, if the oxidizing agent in the powder is saltpeter. How do I find their amounts?
formula for black powder?
The combustion equation for black powder is complex; a simplified balanced equation is as follows:
2 KNO3 + S + 3 C → K2S + N2 + 3 CO2
You can find other equations here:
https://en.wikipedia.org/wiki/Gunpowder#Chemical_reaction
mols saltpeter (KNO3) = g/molar mass = ?
Using the coefficients in the balanced equation, convert mols KNO3 to mols CO2.
Then convert mols CO2 to grams; i.e., grams CO2 = mols CO2 x molar mass CO2 = ?
Do the same for SO2.
It isn't possible to determine O2 formed since this particular equation does not generate O2. You will need to find an equation that generates O2 to do that. My frank opinion, although I'm not an arms expert, is that no excess O2 is generated; i.e., I suspect ALL O2 is used to form CO2, SO2, NO or NO2, etc.
To find the amounts of oxygen, carbon dioxide, and sulfur dioxide generated when the firework bursts, you need to consider the chemical reaction that occurs during the combustion of black powder.
The main components of black powder are sulfur, charcoal, and saltpeter (potassium nitrate), with the following chemical formula:
6KNO3 + C7H4O + S → K2SO4 + K2CO3 + N2 + 4CO2 + 2H2O
From the given information, we only know the mass of the black powder (280 g), and we need to find the amounts of the individual products. To determine the quantities, you need to use stoichiometry and the molar masses of the substances involved.
1. Determine the molar masses of the relevant substances:
- Potassium nitrate (KNO3): 101.11 g/mol
- Charcoal (C7H4O): 92.11 g/mol
- Sulfur (S): 32.07 g/mol
- Potassium sulfate (K2SO4): 174.26 g/mol
- Potassium carbonate (K2CO3): 138.21 g/mol
- Nitrogen (N2): 28.02 g/mol
- Carbon dioxide (CO2): 44.01 g/mol
- Water (H2O): 18.02 g/mol
2. Convert the mass of black powder to moles:
- Moles of black powder = Mass of black powder / Molar mass of black powder
- Moles of black powder = 280 g / (101.11 g/mol + 92.11 g/mol + 32.07 g/mol)
3. Use stoichiometry to determine the moles of each product:
- Following the balanced equation, you can see that:
- For every 6 moles of potassium nitrate, you will have:
- 1 mole of potassium sulfate (K2SO4)
- 1 mole of potassium carbonate (K2CO3)
- 1 mole of nitrogen gas (N2)
- 4 moles of carbon dioxide (CO2)
- 2 moles of water (H2O)
4. Convert the moles of each product to mass:
- Mass of each product = Moles of the product × Molar mass of the product
By following these steps and applying the appropriate calculations, you can determine the amounts of oxygen, carbon dioxide, and sulfur dioxide generated when the firework bursts.
To find the amounts of oxygen (O2), carbon dioxide (CO2), and sulfur dioxide (SO2) generated when the firework bursts, you need to know the chemical equation for the reaction between the black powder and the oxidizing agent (saltpeter).
The chemical formula for black powder is typically written as KNO3 (saltpeter) + S + C → K2CO3 + N2 + SO2.
Now, let's find the molar masses of the compounds involved:
- KNO3 (saltpeter) = 101.11 g/mol (molar mass of potassium nitrate)
- S (sulfur) = 32.06 g/mol (molar mass of sulfur)
- C (carbon) = 12.01 g/mol (molar mass of carbon)
- K2CO3 = 138.21 g/mol (molar mass of potassium carbonate)
- N2 = 28.02 g/mol (molar mass of nitrogen)
- SO2 = 64.06 g/mol (molar mass of sulfur dioxide)
To find the amount of each product, you'll need the mole ratio of the reactants and products, which can be obtained from the balanced chemical equation. From the equation, you can see that 1 mole of KNO3 produces 2 moles of K2CO3, 1 mole of N2, and 1 mole of SO2.
Now, let's calculate the moles of KNO3 in 280 g:
moles of KNO3 = mass of KNO3 / molar mass of KNO3
= 280 g / 101.11 g/mol
≈ 2.77 mol
Using the mole ratio, you can find the moles of K2CO3, N2, and SO2 produced.
moles of K2CO3 = 2.77 mol
moles of N2 = 2.77 mol
moles of SO2 = 2.77 mol
Finally, you can find the amounts (in grams) of each product:
mass of K2CO3 = moles of K2CO3 * molar mass of K2CO3
mass of N2 = moles of N2 * molar mass of N2
mass of SO2 = moles of SO2 * molar mass of SO2
Using the respective molar masses calculated earlier, you can determine the exact amounts of oxygen, carbon dioxide, and sulfur dioxide generated when the firework bursts.