Question

Phosphorus burns in air to produce a phosphorus oxide (P4O10) in 4​P + 5O2 --> P4O10.

If 0.489 mol of phosphorus burns, what mass in grams of oxygen is used?

Answer 1

9.78 grams of oxygen is used in the reaction

Step-by-step explanation:

The balanced chemical equation is:4P + 5O2 → P4O10From the equation, we can see that the molar ratio of phosphorus to oxygen is 4:5, which means that for every 4 moles of phosphorus, we need 5 moles of oxygen to react completely.

Given that 0.489 mol of phosphorus is burned, we can use the molar ratio to calculate the amount of oxygen required:5 mol O2 / 4 mol P × 0.489 mol P = 0.61125 mol O2Therefore, 0.61125 mol of oxygen is required to react completely with 0.489 mol of phosphorus.

Now we can use the molar mass of oxygen (16 g/mol) to convert the amount of oxygen from moles to grams:0.61125 mol O2 × 16 g/mol = 9.78 gTherefore, approximately 9.78 grams of oxygen is used in the reaction.