<p>No this question was on form O and I don’t think they put the same question with different number answers?</p>
<p>@acttest KI? Yeah, I had a different test</p>
<p>@PoisonIvy20 Either 4 or 7… I forget which. I’m leaning towards 4.</p>
<h1>1, 2, 3 on FRQ is worth 10 points.</h1>
<h1>4-7 is worth 4 points</h1>
<p>@Hawkace thats strange.i thought we all have the same questions.</p>
<p>The reason it was 30.5% was because just taking the molar mass of I over the molar mass of KI was not correct because there was a unknown amount of a sugar in the KI making it impure. </p>
<p>You had to use the mass of the precipiate and then stocihmetry to calculate the mass of I, then over whatever the mass of the tablet was, giving you around 30%</p>
<p>Is it cool if we work through probs on here or will we get our scores voided</p>
<p>Frack. I know what I did wrong. I think that I did Cl- instead of I-. Damnit. </p>
<p>There’s 2 points down the drain. Goddamnit. I want that 5. </p>
<p>If so for 7, did the fact that the half life did not change when the pressure did show that it’s first order? </p>
<p>@glogounov You are not, per the CB’s rules, allowed to share or discuss any questions from the test. FRQ can be discussed 2 days after the test, should the CB upload the questions to their website. </p>
<p>Share at your own risk.</p>
<p>I just said that half life didnt depend on conc. of whatever substance it was with the 30 sec i had left</p>
<p>IDK if this was right but the fact the half life didn’t change when the pressure was doubled showed it was first order. </p>
<p>Quick. Someone tell me a strategy of how to deal with stress when you know that you messed something up on the FRQ. </p>
<p>I need somethin to do listen to. I’m freakin out. I want that 5. </p>
<p>@needagoodscore wow i did that exactly and then i changed my answer because i forgot about the water. Im an idiot.</p>
<p>Who else got 30.5% Iodine? I’m paranoid I forgot to multiply by two when I switched between mol PbI2 and I but I’m not sure if I did…</p>
<p>@3mpathy That’s what I got and I multiplied by two. :)</p>
<p>I remember why I said that now. for trial 1 the inital pressure was 300 and for trial the initial pressure was 600. In trial 1, 150 torr was reacted in 100s but in trial 2 300 torr was reacted in 100s. Therefore, the rate doubled with double the concentration</p>
<p>3mpathy, 30.5 is correct don’t listen to them I promise your good. Anyone know whst the deal is when 55 instead of 50? Couldn’t more ionize so there’s more I- so eventually a slightly higher percent mass</p>
<p>Hmm that makes sense. How about the whole activation energy business. Would saying the +15 kelvin mean the activation energy was reached and that’s why the half life was half of what it was </p>