When 23g of C8H18 is combusted at STP, how many liters of carbon dioxide is produced?

Answer 1

2C8H18 + 25O2 ==> 16CO2 + 18H2O

mols C8H18 = grams/molar mass = ?

Using the coefficients in the balanced equation, convert mols C8H18 to mols CO2.
Now convert mols CO2 to g. grams CO2 = mols CO2 x molar mass CO2.