Calculate the Change in Enthalpy Associated with the Combustion of Ethanol

How can we calculate the change in enthalpy associated with the combustion of ethanol?

Given data: Mass of ethanol = 322 g, Molar mass of ethanol = 46.07 g/mol, Heat of combustion of ethanol = -1367 kJ/mol.

Calculating the Change in Enthalpy:

To calculate the change in enthalpy associated with the combustion of ethanol, we need to use the heat of combustion (∆Hc) of ethanol and the molar mass of ethanol.

The balanced equation for the combustion of ethanol is C2H5OH + 3O2 -> 2CO2 + 3H2O.

The molar mass of ethanol (C2H5OH) is approximately 46.07 g/mol. We have 322 g of ethanol, which is equal to 322 g / 46.07 g/mol = 6.99 moles of ethanol.

The heat of combustion (∆Hc) of ethanol is approximately -1367 kJ/mol.

Now we can calculate the change in enthalpy (∆H) associated with the combustion of 322 g of ethanol: ∆H = ∆Hc x moles of ethanol ∆H = -1367 kJ/mol x 6.99 mol ∆H = -9554 kJ

Therefore, the change in enthalpy associated with the combustion of 322 g of ethanol is approximately -9554 kJ. The negative sign indicates that the reaction is exothermic, meaning it releases energy in the form of heat.

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