Calculate the energy released per gram of propane when it is burned in a combustion reaction. The chemical formula for propane is C3H8.

Write and balance the equation.

Then dHrxn = (n*dHf products) - (n*dHf rreactants). You can look up the values for delta H formation in your text/notes.
The answer you get for dHrxn will be in kJ/mol. Convert to kJ/gram.

To calculate the energy released per gram of propane when it is burned in a combustion reaction, we need to use the enthalpy of combustion value for propane.

The balanced combustion equation for propane is as follows:

C3H8 + 5O2 -> 3CO2 + 4H2O

According to the balanced equation, 1 mole of propane (C3H8) produces 3 moles of carbon dioxide (CO2) and 4 moles of water (H2O) when fully combusted.

Now, we need to find the enthalpy of combustion (ΔHc) value for propane. The standard enthalpy change of combustion of propane is approximately -2220 kJ/mol.

Next, we can calculate the energy released per mole of propane using the enthalpy of combustion:

Energy released per mole of propane = -2220 kJ/mol

Since the molecular weight of propane is approximately 44.1 g/mol, the energy released per gram of propane can be calculated as follows:

Energy released per gram of propane = (Energy released per mole of propane) / (Molecular weight of propane)

Energy released per gram of propane = (-2220 kJ/mol) / (44.1 g/mol)

Finally, we can calculate the value:

Energy released per gram of propane ≈ -50.1 kJ/g

So, approximately 50.1 kJ of energy is released per gram of propane when it is burned in a combustion reaction.

To calculate the energy released per gram of propane when it is burned, we need to use the concept of molar mass and the heat of combustion.

1. First, calculate the molar mass of propane (C3H8):
- The atomic mass of carbon (C) is 12.01 g/mol.
- The atomic mass of hydrogen (H) is 1.01 g/mol.
- Since propane has three carbon atoms and eight hydrogen atoms, the molar mass of propane is:
Molar mass of propane (C3H8) = (3 * 12.01 g/mol) + (8 * 1.01 g/mol) = 44.11 g/mol

2. Next, find the heat of combustion for propane. The heat of combustion is the amount of heat released when one mole of a substance is completely burned. For propane, the heat of combustion is typically given as -2220 kJ/mol.

3. Now, we can calculate the energy released per gram of propane:
- Divide the heat of combustion (-2220 kJ/mol) by the molar mass of propane (44.11 g/mol) to find the energy released per mole of propane:
Energy released per mole of propane = -2220 kJ/mol / 44.11 g/mol = -50.32 kJ/g

Therefore, the energy released per gram of propane when it is burned in a combustion reaction is -50.32 kJ/g. The negative sign indicates the release of energy during the combustion process.