Question

Glucose, C6H12O6, is a good source of food energy. When it reacts with oxygen, carbon dioxide and water are formed. How many liters of CO2 are produced when 126 g of glucose completely react with oxygen? C6H12O6(s) + 6O2(g) → 6CO2(g) + 6H2O(l) + 673 kcal

a.15.7 L
b.94.1 L

Answer 1

The number of liters produced when 126g of glucose is completely reacted with O2 is calculated as follows
find the moles of C6H12O6 used that is moles = mass /molar mass
= 126g /180 g/mol = 0.7 moles

from the equation
C6H12O6 +6O2 = 6CO2 +6 H2O
the reacting ratio of C6H12O6 to Co2 is 1:6 therefore the moles of CO2 = 0.7 x6/1= 4.2 moles

At STP 1 moles of a gas = 22.4 L
what about 4.2 L = how many liters
cross multipication
= (4.2moles x 22 .4 L)/ 1mole = 94.1 L