phosphorus (12.28g) reacts with excess of oxygen gas to form 21.04 grams of diphosphorus penatoxide. what is the theoretical yile in grams of this reaction?
im not sure how exactly do you start this?
*yield
You knew exactly what to do in the limiting reagent problem. These are simpler since there is only one reagent to worry about.
Convert 12.28 g phosphorus to moles. moles = grams/molar mass. This is the limiting reagent because you have only this reagent given and the other is "all you need."
Use the coefficients in the balanced equation to convert moles phosphorus to moles P2O5.
Then g P2O5 = moles P2O5 x molar mass P2O5. This is the theoretical yield in grams. Most problems that show a yield and ask for theoretical yield also want the percent yield. IN this case it is %yield = (actual yield/theoretical yield)*100 = ?
thanks, i got 74.77% :)
That looks ok to me.
To determine the theoretical yield of a chemical reaction, you need to calculate the maximum amount of product that can be formed, assuming the reaction goes to completion and all reactants are completely converted into products.
To begin, you should first write the balanced chemical equation for the reaction. In this case, the reaction is between phosphorus and oxygen gas to form diphosphorus pentoxide (P4 + O2 → P4O10).
Next, calculate the molar mass of each compound. The molar mass of phosphorus (P4) is 123.88 g/mol, and the molar mass of diphosphorus pentoxide (P4O10) is 283.89 g/mol.
Using the balanced equation and the molar masses, you can determine the stoichiometry of the reaction. The stoichiometry tells you the ratio in which the reactants and products combine. In this case, the balanced equation tells us that 1 mole of phosphorus reacts with 5 moles of oxygen gas to form 1 mole of diphosphorus pentoxide.
Now, you can calculate the moles of phosphorus. Given that you have 12.28 g of phosphorus, divide this mass by the molar mass of phosphorus:
moles of phosphorus = mass of phosphorus / molar mass of phosphorus = 12.28 g / 123.88 g/mol = 0.099 moles
Since you have excess oxygen, you need to determine how much oxygen is required to react with the calculated moles of phosphorus. Using stoichiometry, 0.099 moles of phosphorus require 0.099 moles × 5 moles = 0.495 moles of oxygen gas.
Finally, you can calculate the theoretical yield of diphosphorus pentoxide using the moles of oxygen gas and the molar mass of diphosphorus pentoxide:
theoretical yield = moles of oxygen × molar mass of diphosphorus pentoxide = 0.495 moles × 283.89 g/mol = 140.41 grams
Therefore, the theoretical yield of diphosphorus pentoxide in this reaction is 140.41 grams.