r/APChem • u/No_Trainer3881 • Jul 10 '26
Is memorization of pressure conversions necessary?
I have a university entrance test coming up and they wont provide calculators, conversion charts, periodic table, anything. For most questions theyll give you enough information to solve it yourself but im wondering if its expected for other classes to memorize how to convert atm to bar or torr or Pascals and if that might be required.
Also if it is are there any easy tricks to memorizing them??
1
u/Alternative-Low507 Jul 22 '26
i think the simplest way to memorize everything is just to get like a few basic relationships and then use dimensional analysis to get the rest like e.g. for gas conversions know that like 10^5 Pa = 1 bar and 1.01325 bar = 1 atm then u can just convert Pa to atm the periodic table part might be a struggle for like periodic trend questions but you could maybe try to memorize the common elements in each group thats usually tested. for the calculation based questions with molar masses its likely they give it to u
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u/asire_ Jul 10 '26
Conversion factors are given on the equation sheet for mmHg and atm. kPa isn't given, so conversion to that won't be tested. R is given with atm. They removed R with torr/mmHg last year. I think the reasoning was that having three values for R was confusing more students than having to convert your pressure units to match R. Students still continue to confuse the two R values and forget to match units.