how many moles of O2 are needed to produce 12.4 g of P2O5 from the equation P4 + 5O2 = 2P2O5?
To find the number of moles of O2 needed to produce 12.4 g of P2O5, we first need to calculate the molar mass of P2O5.
The molar mass of P2O5 is the sum of the atomic masses of its constituent elements:
Mass of P = 30.97 g/mol (atomic mass of phosphorus)
Mass of O = 16.00 g/mol (atomic mass of oxygen)
Molar mass of P2O5 = (2 * Mass of P) + (5 * Mass of O)
= (2 * 30.97 g/mol) + (5 * 16.00 g/mol)
= 62.00 g/mol + 80.00 g/mol
= 142.00 g/mol
Next, we can use the stoichiometry of the balanced chemical equation to determine the number of moles of O2 required to produce 1 mole of P2O5.
The balanced equation is: P4 + 5O2 → 2P2O5
From the equation, we see that 5 moles of O2 react to produce 2 moles of P2O5.
Now, we can use dimensional analysis to find the number of moles of O2 needed.
Given:
Mass of P2O5 = 12.4 g
Molar mass of P2O5 = 142.00 g/mol
Number of moles of P2O5 = Mass of P2O5 / Molar mass of P2O5
= 12.4 g / 142.00 g/mol
= 0.087 moles of P2O5
According to the stoichiometry of the equation, we need 5 moles of O2 to produce 2 moles of P2O5.
So, we can set up a proportion:
5 moles O2 / 2 moles P2O5 = X moles O2 / 0.087 moles P2O5
Solving for X:
X = (5 moles O2 / 2 moles P2O5) * 0.087 moles P2O5
X = 0.2175 moles of O2
Therefore, 0.2175 moles of O2 are needed to produce 12.4 g of P2O5 from the given equation.
find the molar mass of P2O5
12.4 / molar mass = moles
each mole of P2O5 uses 5/2 mol O2 for production