Question

Gaseous ethane CH3CH3 will react with gaseous oxygen O2 to produce gaseous carbon dioxide CO2 and gaseous water H2O. Suppose 1.8 g of ethane is mixed with 12.6 g of oxygen. Calculate the maximum mass of water that could be produced by the chemical reaction. Be sure your answer has the correct number of significant digits.

Answer 1

the balanced equation is as follows

2 C2H6 + 7 O2 -----------------------> 4 CO2 + 6 H2O

no of moles = mass /molar mass

for C2H6 = 1.8 g / 30.07g/mol => 0.05986 moles

for O2 = 12.6 g / 32g/mol => 0.39375 moles

2 mol C2H6 -----------------------> 6 mol H2O

0.05986 mol ----------------------->?

=> 0.05986 * 6 / 2

=> 0.1795 moles

7 mol O2 ----------------> 6 mol H2O

0.39375 mol ----------------->?

=> 0.39375 * 6 / 7 => 0.3375 moles

limiting reactant is C2H6

maximum mass of H2O is => 0.1795 moles * 18 g/mol => 3.23245 g

answer => 3.23 grams

Answer 2