@elyvine help
@APScholar18 I guessed on this one, but I could definitely eliminate A because that’s unrelated to pKw and eliminate B because Kw in the formula table has a note “at 25 degrees” next to it and I just knew it changed with different temperatures because K is affected by temperature. Not sure why D is right at all though, so if someone could explain that’s be appreciated!
@SippinCoffee No, this is from the course description of AP Chem:
“Electrons in atoms have an intrinsic property known as spin that can result in atoms having a magnetic moment. There can be at most two electrons in any orbital, and these electrons must have opposite spin.”
And apparently the magnetic moment’s strength increases with an increase in the number of unpaired electrons.
@APScholar18 I can’t tell if you actually don’t know basic concepts like this, or if you’re just trying to waste our time. Why is a triple bond stronger? Are you serious??? Get real here. We’re 8 hours away from the exam.
@APScholar18 I think the answer is C, but idk where you guys are finding the answers on the drive.
Anyways, my explanation is that pKw increases as temp increases. So, less H3O+. Less H3O+, higher pH.
@elyvine that makes sense. I guess it threw me off because I didn’t think any reaction was happening between the two gasses in there, but I guess it doesn’t matter since there’s still an equilibrium to be reached somehow haha
@APScholar18 pH stands for percent concentration of H+ so pKw stands for percent concentration of Kw or the equilibrium for pure water, we see that on the chart as you increase T, pKw decreases. This means that as T increases, the percent concentration of Kw, or the equilibrium for pure water, decreases. Since they’re asking for pH ONLY (not pOH), we’re only worried with how the H+ concentration changes. Since a lower Kw means less H+ from the auto ionization, pH decreases.
@Frigidcold The answer is D.
@APScholar18 @apactstudent Have to agree 
Sorry, I meant as in you have the balanced equation and you have both delta G and delta H values, for example delta H is -400 KJ/mol and delta G is -500 KJ/mol so you would go from grams of substance to mol, then mol of substance to Kj/mol of the rxn, but would you use delta G or H? I thought it was H before, but in this question on PR it uses delta G
@elyvine I thought more H+ means a lower pH?
Can someone explain #19 to me? I thought it was A but the answer is C.
And if possible can someone give me a short paragraph crash course on what happens when you mix a weak acid with a strong base, or a weak base with a strong acid? I used to think that they would cancel out but that is incorrect. Why is that? Thank you everyone.
Wait what?! Doesn’t lower [H+] mean higher pH, or do I have no concept of acids and bases?
@apactstudent not gonna lie that gave me a good laugh
@APScholar18 Just believe in yourself and what you already know. You probably know more than you realize so don’t fret too much. You can only cram so much in one night 
@Frigidcold you have it all wrong. The pKw is decreasing with increasing temperature. Since there is a negative log relationship between Kw and pKw, as pKw decreases, Kw increases, which favors the products (H+ and OH-).
I just don’t understand why people post on the forum the night before the exam with all these questions. Shouldn’t this all have been sorted out with your teacher a while ago? Tbh, at this point, if you don’t know chemistry, you’re NOT going to know it by tomorrow morning.
@Batmen HCl is a strong acid, so it will give it’s H+ to water regardless. HClO2 is weak, so it will need a strong base, KOH, to dissociate more completely. So, KOH will take H+ from HClO2, leaving more ClO2-.
@apactstudent I am only trying to improve my essay scores by thoroughly understanding explanations I got a 51/60 on the 2013 MC.
is 2012 mc too different to be relevant?
@apactstudent Lol, thanks. Got the question right when our teacher gave this to us as a graded test. Guess it’s just late