Question

Olive Oil is almost pure glyceryl trioleate, C57H104O6. The equation for the combustion of glyceryl trioleate is: C57H104O6 + 80 O2 -> 57 CO2 + 52 H20.

What is the change in the internal energy, delta E, in kJ for the combustion of 1 mol glyceryl trioleate?

ANS: -1.93*10^3 kJ/mol glycerol trioleate

I was provided the answer, but I don't know how to solve. Please show your work so I can understand.

Previous question before this was: 1.000 g olive oil is completely burned in pure oxygen in a bomb calorimeter. The temperature of the water bath increases from 22.000 degrees Celsius to 22.241 degrees Celsius. How many dietary calories are in olive oil per gram or kcal/g olive oil? The heat capacity is 9.032kJ/degrees Celsius.

I solved it and my answer was -0.521 Cal/g

Answer 1

Ans :

Olive oil has -0.521 Cal/g

1 cal = 4.184 J

so -0.521 Cal = -0.521 x 4.184 J = -2.179 J

Molar mass of olive oil = 885.43 g/mol

so one mole of olive oil on combustion will cause the change in internal energy :

= molar mass x dietary calories/g

= 885.43 g/mol x (-2.179 J/g)

= -1930 J/mol

in KJ/mol = (-1930 /1000) KJ/mol

= -1.93 x 10³ KJ/mol