Two nonpolar organic liquids, hexane (C₆H₁₄) and heptane (C₇H₁₆), are mixed. (a) Do you expect ∆H_soln to be a large positive number, a large negative number, or close to zero? Explain.

Video transcript

hi everyone for this problem. It reads to organic liquids with a very similar London dispersion force are mixed. What is the expected change in entropy of solution of the mixture explain. Okay, so we're looking for the expected change in entropy of the solution. So let's recall the change in entropy of our solution is going to equal the sum of the change in entropy of our salute plus the change in entropy of our solvent plus the change in entropy of our mixture. Okay. Since both of the liquids have a very similar London dispersion force, which is what we're told here. They have a very similar London dispersion force. The energy required to separate them individually and the energy released when they are mixed are approximately equal. Okay. And so what this means is our change in entropy of the solute plus the change in entropy of our solvent is going to equal. A negative change in entropy of our mixture. And what this translates to is our change in entropy of the solution is nearly zero. Okay. And so the correct answer choice here is going to be a and that reads the expected change in entropy of the solution will be close to zero because the change in entropy of the solute and solvent will be almost equal. Okay, so a is our correct answer here. And that is the explanation. That's the end of this problem. I hope this was helpful