Answer:
NaOH: 22.99 + 16.00 + 1.008 = 40.00 g/mol
H₂O: 2(1.008) + 16.00 = 18.02 g/mol
C₆H₁₂O₆: 6(12.01) + 12(1.008) + 6(16.00) = 180.2 g/mol
CaSO₄: 40.08 + 32.06 + 4(16.00) = 136.1 g/mol
Mg₃(PO₄)₂: 3(24.33) + 2(30.97) + 8(16.00) = 262.9 g/mol
The numbers I added up are the atomic numbers you can find on the periodic table. Multiply the atomic numbers by however many atoms of a element you have.
1) Convert 12.9 liters of Oxygen to mol at the given conditions:
PV = nRT ⇒ n = PV/RT
n = [1.2atm*12.9 l] / [0.082 atm l /K mol * 297K]
n = 0.636 mol of O2
2) use the stoichiometry derived from the balanced chemical equation
1mol C2H4 / 3 mol O2 = x mol C2H4 / 0.636 mol O2
x = 0.636 / 3 mol O2 = 0.212 mol O2.
Answer: 0.212 mol O2
The answer is Air and Gravity
