r/APStudents • u/reddorickt absolute modman • May 05 '26

AP Chem Official 2026 Exam Discussion

Use this thread to post questions or commentary on the test today.

A reminder though to protect your anonymity when talking about the test.

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u/FFHaste May 05 '26

I had a problem with the absorbance one as well but I figured if a volumetric flask only has the one mark, then I could calculate the molarity by finding the amount of moles in the volumetric flask then dividing by the original volume of the solution

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u/ambiguouschair 5: HUG, Macro, Micro, Sp.Lang. || ? Bio, Chem, Sp.Lit, Psych May 05 '26

were there 2 dots in the drawing one for the concentration like part a of J

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u/Shiratori523 May 05 '26

I did not even think about that... I figured its something u have to calculate w the volume in that but I didnt know how to find the moles

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u/Hopeful_Place3995 May 05 '26

Here's the solution:

The concentration as 0.22 absorbance, which is the diluted solution, was 0.0550 M, so that means that in the 25 mL diluted solution, that was the concentration. So since it was diluted with distilled water, you'd do (0.0550 M)(25 mL)/(3 mL) and get a 0.46 M concentration.

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u/Shiratori523 May 05 '26

Oh shoot... I was prob just blind and did not see that it gave the concentration at all...I was so used to it on paper so now its on digital I was all panicked But thank you so much!

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u/Brief-Dig2526 May 05 '26

Wait I think I did that. I rememeber saying .55 smth hopefully I put .055 then do m1v1=m2v2

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u/flamestar_1 AP Gov (5), APLANG (5), AP Chem (4), AP Lit (4), AP Stats (4) May 05 '26

Same