Equation: C3H8 + 5O2 --- 3CO2 + 4H2O

Question

Equation: C3H8 + 5O2 --- 3CO2 + 4H2O

a) How many moles of CO2 are produced from 14.8 g of C3H8?

b) How many moles of CO2 are produced from 3.44 g of O2?

c) If you mixed 14.8 g C3H8 with 3.44 g O2, which would run out first? (In other words, which one is the limiting reactant?) How do you know?

Answer 1

14.8 grams of C3H8 is 0.34moles of C3H8.

14.8g/44gmol-1=0.34moles

a.)the mole ration of C3H8 to CO2 is 1:3 , 0.34moles of C3H5 will give ).34 moles*3 CO2=1mole of CO2

b.)The mole ratio for oxygen to CO2 is 5:3 moles , 3.44 grams of oxygen will give 0.0645 moles of CO2

0.01075 moles of oxygen *3/5=0.0645moles.

c.)The reaction between C3H8 and oxygen is 1:5 moles.There are 0.34 moles of C3H8 in 14.8 grams of C3H8 and 0.108moles of oxygen in3.44 grams of oxygen.0.34 moles of C3H8 needs 1.7 moles of oxygen .Since 0.108 present oxygen is the limiting reagent.