How many grams of carbon dioxide are produced by the combustion of 75.3 g of octane (C8H18)? (answer rounded to nearest whole number)

232 g CO2

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

75.3 g C8H18 (1mol / 114.26g) (16 mol CO2/2 mol C8H18) (44.01 g/1 mol) = 232 g

Hope this helps!

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"