Find the change in internal energy for this reaction. Enter in kJ. 2C2H2(g) + 5O2(g) → 4CO2(g) + 2H2O(l)

Enthalpy of reaction= -2599 kJ

Oh boy, I can feel the heat rising! To find the change in internal energy for this reaction, we need to use a pretty awesome equation called the First Law of Thermodynamics. It states that the change in internal energy (ΔU) of a system is equal to the heat (q) added to the system minus the work (w) done by the system.

But here's the fun part: for this reaction, we're given the enthalpy of reaction (ΔH), which is the heat exchanged at constant pressure. So fortunately, we don't need to calculate the work done here. Woo-hoo!

The change in internal energy (ΔU) is equal to the enthalpy change (ΔH) minus the work done (w). Since we're at constant pressure, we can assume that the work done is negligible, so the change in internal energy (ΔU) is pretty much equal to the enthalpy change (ΔH).

So in this case, the change in internal energy (ΔU) is -2599 kJ. Remember to keep those negative signs in mind. Enjoy the heat, my friend!

To find the change in internal energy for a reaction, you can use Hess's Law. According to Hess's Law, the change in internal energy (ΔU) for a reaction is equal to the enthalpy change (ΔH) of the reaction minus the work done (w) by the system.

In this case, the enthalpy of reaction (ΔH) is given as -2599 kJ. To find the change in internal energy, we also need to know the work done by the system. However, without any information about the pressure or volume changes, we assume that the work done is negligible (w = 0).

Therefore, the change in internal energy (ΔU) for this reaction can be approximated as:

ΔU = ΔH - w
ΔU = -2599 kJ - 0
ΔU = -2599 kJ

The change in internal energy for this reaction is -2599 kJ (negative because the reaction is exothermic).

Correct answer is 394kJ

dE = q + w

You know q.
w is -p(Vfinal-Vinitial)
You have 7 mols gas on the left at 22.4 L/mol if this is at STP. You have only 4 mols gas on the right. That should give you Vfinal and Vinitial and work will be in units of L*atm. Multiply that by 101.325 to convert L*atm to J. Substitute into dE = q + w. Convert J to kJ.