Question

Phosphorus will react with oxygen to form diphosphorus pentoxide, P2O5 4P(s)+5O2(g) → 2P2O5(s) How many grams of P2O5 are formed when 4.89 g of P react with excess oxygen?

Answer 1

Answer:

11.2 g

Explanation:

Given,

Mass of P = 4.89 g

Molar mass of $P$ = 30.9738 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$Moles= \frac{4.89\ g}{30.9738\ g/mol}$

$Moles_{P}= 0.158\ mol$

According to the reaction shown below as:-

$4P_{(s)}+5O_2_{(g)}\rightarrow 2P_2O_5_{(s)}$

4 moles of P on reaction forms 2 moles of diphosphorus pentoxide

Also,

1 mole of P on reaction forms 2/4 mole of diphosphorus pentoxide

0.158 moles of P on reaction forms $\frac{2}{4}\times 0.158$ moles of diphosphorus pentoxide

Moles of diphosphorus pentoxide = 0.079 moles

Molar mass of diphosphorus pentoxide = 141.9445 g/mol

Mass = Moles * Molar mass = 0.079 moles * 141.9445 g/mol = 11.2 g