The complete combustion of 1.283g of cinnamaldeyde (C9H8O, one of the compounds in cinnamon) in a bomb calorimeter (Ccalorimeter=3.841 kJ/C) produced an increase in temperature of 130.32 C. Calculate the molar enthalpy of combustion of cinnamaldehydy (delta H comb) (in kilojoules per mole on cinnamaldehyde)

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To calculate the molar enthalpy of combustion (ΔHcomb) of cinnamaldehyde (C9H8O), you need to use the information provided, such as the mass of cinnamaldehyde, the heat capacity of the calorimeter, and the change in temperature.

Here's how you can approach this calculation step-by-step:

1. Convert the mass of cinnamaldehyde to moles:
Determine the molar mass of cinnamaldehyde (C9H8O):
Molar mass of carbon (C) = 12.01 g/mol
Molar mass of hydrogen (H) = 1.008 g/mol
Molar mass of oxygen (O) = 16.00 g/mol

Molar mass of cinnamaldehyde (C9H8O) = (9 * 12.01 g/mol) + (8 * 1.008 g/mol) + (1 * 16.00 g/mol)
Molar mass of cinnamaldehyde = 132.16 g/mol

Now, calculate the number of moles of cinnamaldehyde:
Moles of cinnamaldehyde = Mass of cinnamaldehyde / Molar mass of cinnamaldehyde

Moles of cinnamaldehyde = 1.283 g / 132.16 g/mol

2. Calculate the heat released by the combustion of cinnamaldehyde in the calorimeter:
Heat released = Ccalorimeter * ΔT

Ccalorimeter is the heat capacity of the calorimeter, given as 3.841 kJ/°C
ΔT is the change in temperature, given as 130.32 °C

Heat released = 3.841 kJ/°C * 130.32 °C

3. Calculate the molar enthalpy of combustion (ΔHcomb):
ΔHcomb = Heat released / Moles of cinnamaldehyde

ΔHcomb = (3.841 kJ/°C * 130.32 °C) / (1.283 g / 132.16 g/mol)

Make sure to convert grams to moles before performing the calculation.

Solve this expression to get the molar enthalpy of combustion of cinnamaldehyde (ΔHcomb) in kilojoules per mole (kJ/mol).