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