What is the maximum amount in moles of p2o5 that can theoretically be made from 112 g of p4 and excess oxygen?

1.808 moles

Explanation:

The equation is:-  4P + 5 O2 = 2 P2O5

Number of moles = Mass of substance / Mass of one mole

Given, mass of P₄ = 112 g

Mass of one mole of P₄ = 30.97 g/mol

So, number of moles of P₄ = 112/ 30.97 = 3.616 moles

For 2 moles of  P₂O₅, the number of moles required for P₄ will be 4 moles.

∴ Number of moles of P₂O₅ = 1/2*(number of moles of P₄)

                                                =1/2 * (3.616) = 1.808 moles

So, maximum amount of moles required is 1.808 moles

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.