To solve this question we need:
Step 1 - balance the equation reaction
Step 2 - Transform 5.6 grams of oxygen into moles
Step 3 - look at the reaction equation ratio to find out how many moles of phosphorus ar required to react with 5.6 grams of oxygen
Step 1:
We need to have the same amount of each element on both sides of the equation.
4 P + 5 O2-- > P4O10
Step 2:
We need to use the following formula:
mole = mass/molar mass
molar mass of O2 = 2x16 = 32 g/mol
mole = 5.6/32
mole = 0.175 moles of O2
Step 3:
According to the equation, we have:
4 moles of phosphorus reacting with 5 moles of O2
4 moles P --- 5 moles O2
x moles P --- 0.175 moles of O2
5x = 0.7
x = 0.14 moles
Answer: 0.14 moles of phosphorus