If 4 moles of P is used by 5 mole of O2
then....0.489 moles will be used by 5/4 × .489 = .611 moles of O2
so .611 moles
so if 4 moles of P is burnt , 1 mole of P4O10 is produced ....so for .489 moles...... .489/4=.122 moles !
so mass will be .122× 283.89 = 34.7 grams
so first ans is .611 moles and second is 34.7 grams !
if you have any problem regarding this , just comment !!!
I believe its A "Air is made up of about 21% oxygen and 78% nitrogen. In this solution, oxygen is the solute and nitrogen is the solvent.
Answer:
The answer is "17200 years".
Explanation:
Given:
Let the half-life of carbon-14, is beta emitter, is
Constant decay
The artifact age 
