Question

What number of moles of O2 are needed to produce 14.2 grams of P4O10 from P? (Molecular weight P4O10 = 284) (A) 0.0500 mole (B) 0.0625 mole (C) 0.125 mole (D) 0.250 mole (E) 0.500 mole

Answer 1

(D) 0.250 mole

Step-by-step explanation:

From molecular weight we know that 1 mole of P4O10 wights 284 grams. So

`14.2 g P4O10 * (1 mole P4O10)/(284 g P4O10) = 0.05 moles P4O10`

In order to form 1 mole of P4O10 it is necessary 5 moles of O2, so that the number of oxygen atoms are the same.

Knowing that 0.05 moles of P4O10 is formed we need 5 x 0.05 = 0.25 moles of O2