How many grams of O2(g) are needed to completely burn 17.3 g of C3H8(g)?
C3H8 + 5O2 ==> 3CO2 + 4H2O
mols C3H8 = grams/molar mass = ?
Using the coefficients in the balanced equation, convert mols C3H8 to mols O2. That's ?mols C3H8 x (5 mols O2/1 mol C3H8) = ?
Now convert mols O2 to grams. grams = mols x molar mass = ?
To determine the number of grams of O2(g) needed to completely burn 17.3 g of C3H8(g), we need to use the balanced chemical equation for the combustion of propane (C3H8).
The balanced chemical equation for the combustion of propane is as follows:
C3H8(g) + 5O2(g) → 3CO2(g) + 4H2O(g)
From this equation, we can see that for every 1 mole of C3H8, we need 5 moles of O2. To find the number of moles of C3H8 in 17.3 g, we can use the molar mass of C3H8.
The molar mass of C3H8 is calculated as follows:
(3 * Molar mass of carbon) + (8 * Molar mass of hydrogen)
= (3 * 12.01 g/mol) + (8 * 1.01 g/mol)
= 36.03 g/mol + 8.08 g/mol
= 44.11 g/mol
Now, using the molar mass of C3H8, we can find the number of moles of C3H8 in 17.3 g:
Number of moles = Mass / Molar Mass
= 17.3 g / 44.11 g/mol
≈ 0.3923 moles
Since the molar ratio between C3H8 and O2 is 1:5, we can determine the number of moles of O2 needed:
Number of moles of O2 = Number of moles of C3H8 * (5/1)
= 0.3923 moles * 5
≈ 1.9615 moles
Finally, we can find the mass of O2 needed using the molar mass of O2:
Mass of O2 = Number of moles * Molar Mass
= 1.9615 moles * 32.00 g/mol
≈ 62.77 grams
Therefore, approximately 62.77 grams of O2(g) are needed to completely burn 17.3 g of C3H8(g).