for bond energies if tehy give u a diagram of the structure for whatever like c--h--o==h or soemthing amd a chart with c--h=-670 Kj /mol or whatever do u just add all of the KJ/mol together? but what if they only want kJ? would you just multply whatever kJ/mol *1 mol??
how do i go from kJ/mol>>>kJ
delta Ho rxn = sumBE reactants - sum BE products.
You add them togther for reactants and add them together for the products, then subtract as above.
That give you delta H rxn/mol. If you want some other value, say half a mole, divide by 2.
ummm so is delta H kJ/mol?
i want just kJ. do i just mult kJ/mol *1mol?
Yes, you calculate kJ/mol when you do this. If you want kJ per half mole, then multiply by 1/2 and that gives you kJ for whatever problem you are solving. However, it will ALWAYS be kJ/something; i.e., kJ/mol, kJ/g, kJ/500 mg or what have you. If you want to type in your problem it might help explain.
...use the enervy values to estimate delta H for each of the reactions
_______kJ
per mol is understood. So calculate delta H in kJ/mol and just omit the per part.
To calculate the total bond energy for a given molecular structure, you need to determine the number and type of bonds present in the molecule and then sum up their respective bond energies.
In your example, the molecular structure is C--H--O==H, and you have been provided with bond energies in units of kJ/mol. The bond between C and H has an energy of -670 kJ/mol.
First, identify the number of each type of bond in the molecule.
C--H: 2 (There are two C--H bonds)
C--O: 1
O--H: 1
Next, multiply the number of each bond type by its corresponding bond energy.
C--H: 2 * (-670 kJ/mol) = -1340 kJ/mol
C--O: 1 * (bond energy for C--O)
O--H: 1 * (bond energy for O--H)
If you are given the bond energies for C--O and O--H, you can substitute those values in the respective calculations.
Finally, add up all the individual bond energies to get the total bond energy for the molecule. In this case, it would be:
Total bond energy = (-1340 kJ/mol) + (bond energy for C--O) + (bond energy for O--H)
If you want to convert the bond energy from kJ/mol to kJ, you can multiply the bond energy value by the number of moles. For example, if the bond energy is given as x kJ/mol and you have 1 mole of the molecule, then the bond energy in kJ would be x kJ/mol * 1 mol = x kJ.
Remember to pay attention to the units and adjust the calculations accordingly.