2 C3H8O3()+7O2(g) →6 CO2(g) +8 H2O(1)
Shown above is the combustion reaction for glycerol, C3H8O3 (molar mass = 92 g mol 1). A student ignites 5.000 grams of glycerol and uses the energy to heat a sample of
1.000 x 103 g of water in a metal, insulated container. The student measures the change in temperature of the water to be 20.06 °C.
a. Determine the amount of energy transferred to the water. Assume the specific heat capacity of water to be 4.2 J/g°C.
b. Determine the enthalpy of the reaction for the combustion of glycerol, in kJ/molrxn
c. Is energy flowing into the system or out of the system when the combustion reaction occurs? Justify your reasoning.
d. Determine the heat of formation of glycerol, in kJ/mol, using the standard enthalpies of formation given below.

Compound
Standard Enthalpy
of Formation
(kJ mol¹)

CO₂(g)
-380.

H₂O(1)
-290.

H₂O(g)
-140.