Determine how many grams of phosphorus is required to obtain 25 grams of P2O5. find the volume of oxygen.

The synthesis reaction of pentavalent phosphorus oxide is described by the following chemical reaction equation:

4P + 5O2 = 2P2O5;

4 phosphorus atoms interact with 5 oxygen molecules. During the reaction, 2 molecules of pentavalent phosphorus oxide are synthesized.

Let’s calculate the chemical amount of a substance contained in phosphorus oxide weighing 25 grams.

M P2O5 = 31 x 2 + 16 x 5 = 142 grams / mol;

N P2 O5 = 25/142 = 0.176 mol;

To synthesize such an amount of oxide, it is necessary to take 0.176 x 2 = 0.352 mol of phosphorus.

Let’s calculate its weight:

M P = 31 grams / mol;

m P = 0.352 x 31 = 10.912 grams;



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