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What mass of oxygen is needed to produce 0.708 moles of propane?

(Step by step explanation, please )

1 Answer

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C3H8 + 5O2 → 3CO2 + 4H2O

We can see that for every 1 mol of propane, there are 5 mols are oxygen.

If we have 5 grams of propane, how can we convert that into mols? We need to use the molar mass of propane, which is 44.1 g / mol. (12 g/mol x 3 + 1 g/mol x 8)

To convert to mols of propane: n (mols) = mass/molar mass -> 5/44.1 which equals 0.011 mols.

We said that for every 1 mol of propane, there are 5 mols of oxygen, correct? Therefore, 0.011 mols x 5 = 0.57 mols of oxygen needed to react with 5 grams of propane.

To convert 0.055 mols of oxygen to grams, we use the same equation. n = Mass/Molar Mass

0.57 = g/32, solve for the mass in grams of oxygen and we come to: 18.2 grams of Oxygen.

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