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Constants for MCAT?

Started by Kraazy
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Kraazy

Kraazy

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Which constants do you guys think (or know) should be memorized for the MCAT? Should I be spending my time trying to memorize R, Avogadro's, the mass & charge of electons, etc...? According to EK many if not most of the constants will be given on the real MCAT, but I'm sure there are some I should memorize anyway.

Thanks!
 
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Kraazy said:
Which constants do you guys think (or know) should be memorized for the MCAT? Should I be spending my time trying to memorize R, Avogadro's, the mass & charge of electons, etc...? According to EK many if not most of the constants will be given on the real MCAT, but I'm sure there are some I should memorize anyway.

Thanks!
Click to expand...

I'm 99% sure you don't need to have any constants memorized.
 
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I had questions/passages that involved the Planck's constant and it was given...along with the electron charge. Don't bother memorizing them. I don't think I even ended up using the constants (they DO sometimes give you info you don't need to confuse you).
 
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Not quite true that you won't need any constants, but they're very basic. For physics, you might need c = 3e8, pi = 3 (yes, I'm serious), the density of water, a couple others -- see the FAQ in the Study Question Q&A for more. For chemistry, you need Avogadro's number, 273K = 0C, maybe a couple of others; again, check the FAQ.

Good luck.
 
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I believe the one constant they do expect you to know is the Universal Gas Constant (both in 0.082 and 8.314). This was not provided for me.
 
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Wondering what constants are needed to be memorized. If any of this has been changed....

I'm taking Kaplan and they told me to memorize the Faraday's constant, speed of light, etc. so yeah...
 
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Are you sure? would they really give you the speed of light when you need to calculate the frequency of an electromagnetic wave given its wavelength?

I feel like there is only a handful of constants that you need to know...
 
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rockyDoctora said:
Are you sure? would they really give you the speed of light when you need to calculate the frequency of an electromagnetic wave given its wavelength?

I feel like there is only a handful of constants that you need to know...
Click to expand...

yea in the passage or discrete question they give you the constant at the end of hte passage usually in parentheses
 
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rockyDoctora said:
Anyone know where I can find a list of constants to memorize for the MCAT?
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I found this list on another forum:

v sound = 343 m/s @ 20 deg. C, 1 ATM

h (Planck's constant) = 6.6 x 10^-34 J-s

F (Faraday's constant) = 96,500 C/mol

N sub A (Avogadro's #) = 6.02 x 10^23

R (universal gas constant) = .0821 L-ATM/mol-K

e (elementary charge) = 1.6 x 10^-19 C

specific gravity of water = 1000 Kg/m^3 or 1 g/cm^3

g = 10 m/s

G = 6.7 x 10^-11 N-m^2/Kg^2
 
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ErinEmSee said:
I found this list on another forum:

v sound = 343 m/s @ 20 deg. C, 1 ATM

h (Planck's constant) = 6.6 x 10^-34 J-s

F (Faraday's constant) = 96,500 C/mol

N sub A (Avogadro's #) = 6.02 x 10^23

R (universal gas constant) = .0821 L-ATM/mol-K

e (elementary charge) = 1.6 x 10^-19 C

specific gravity of water = 1000 Kg/m^3 or 1 g/cm^3

g = 10 m/s

G = 6.7 x 10^-11 N-m^2/Kg^2
Click to expand...

Much obliged! I wonder how many of these are truly necessary to memorize other than SG, g, the gas constant, and Señor Avocado-gadro's numero. (That's a nifty way to remember how to spell homie's name, btw.) 😎 I feel like the others will always be given. Better to always be safe rather than sorry, though. GL to those that still need to take this beast before it rolls over to a completely different exam in the next few years.
 
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ErinEmSee said:
I found this list on another forum:

v sound = 343 m/s @ 20 deg. C, 1 ATM

h (Planck's constant) = 6.6 x 10^-34 J-s

F (Faraday's constant) = 96,500 C/mol

N sub A (Avogadro's #) = 6.02 x 10^23

R (universal gas constant) = .0821 L-ATM/mol-K

e (elementary charge) = 1.6 x 10^-19 C

specific gravity of water = 1000 Kg/m^3 or 1 g/cm^3

g = 10 m/s

G = 6.7 x 10^-11 N-m^2/Kg^2
Click to expand...

This list is probably sufficient, but there is one additional constant that I would add: Planck's Constant as 4 x 10^-15 eV*s

I seem to remember 2-3 questions on Full lengths where that conversion has come in handy. Sometimes the answers are in given in terms of eV, and you have to do additional conversions if Planck's constant is given in terms of J*s
 
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For both MCATs that I took (4/26 and 5/11), I remember them giving us the constants, with the exception of maybe Avogadro's number. If I were still studying for this exam, as the case may be when scores come out in a few weeks 😳, I would not waste my mental capacities committing these numbers to memory.
 
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QrtrLifeCrisis said:
For both MCATs that I took (4/26 and 5/11), I remember them giving us the constants, with the exception of maybe Avogadro's number. If I were still studying for this exam, as the case may be when scores come out in a few weeks 😳, I would not waste my mental capacities committing these numbers to memory.
Click to expand...

Ah, so sorry to hear you don't have unlimited mental capacities. :meanie:
 
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How about R in equations like PV = nRT and Vroot mean square = square root of 3RT/m ?

R value keeps changing, depending on what kind of equations you are using and this keeps messing me up.
 
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gettheleadout said:
What case? The AAMC recommends we know the common constants. That's pretty much the word of law regardless of anyone's experience with particular exam administrations.
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Word of law is really stretching it... I just went through all the practice AAMCs (excluding 9, which I have no access to) and there are only 3 constant that you would need to solve all the PS questions, one of them is consistently provided an AAMCs later than 4. Memorizing more obviously cannot hurt you but I would classify it as a waste of time.

While not exactly constants, what can really help you is being good at converting metric units, including areas and volumes. Things like cubic meters to liters, square centimeters to square millimeters and so on.

brood910 said:
How about R in equations like PV = nRT and Vroot mean square = square root of 3RT/m ?

R value keeps changing, depending on what kind of equations you are using and this keeps messing me up.
Click to expand...

I know R=8.314 for PV=nRT and none of the other units. If I had to take the test tomorrow I would not bother to learn either of them.
 
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milski said:
Word of law is really stretching it... I just went through all the practice AAMCs (excluding 9, which I have no access to) and there are only 3 constant that you would need to solve all the PS questions, one of them is consistently provided an AAMCs later than 4. Memorizing more obviously cannot hurt you but I would classify it as a waste of time.

While not exactly constants, what can really help you is being good at converting metric units, including areas and volumes. Things like cubic meters to liters, square centimeters to square millimeters and so on.



I know R=8.314 for PV=nRT and none of the other units. If I had to take the test tomorrow I would not bother to learn either of them.
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Just playing it safe! It's easier to know them and be that much more familiar with the numbers and units you'll be working with when you get a problem where you're given a constant you need.
 
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gettheleadout said:
Just playing it safe! It's easier to know them and be that much more familiar with the numbers and units you'll be working with when you get a problem where you're given a constant you need.
Click to expand...

I understand your point very well, just sharing my opinion. From what I've seen, AAMC seems to treat constants as a very auxiliary topic and tends to provide most of them. That combined with my strong dislike of memorizing arbitrary facts (Med School will be just the right place for me, don't you think?) is why I would not bother with anything but c and NA. Everybody else is free to do as they please, of course.

Useless side note: In certain parts of physics we just set h=c=1 and life gets sooo much better. 😎
 
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milski said:
I understand your point very well, just sharing my opinion. From what I've seen, AAMC seems to treat constants as a very auxiliary topic and tends to provide most of them. That combined with my strong dislike of memorizing arbitrary facts (Med School will be just the right place for me, don't you think?) is why I would not bother with anything but c and NA. Everybody else is free to do as they please, of course.

Useless side note: In certain parts of physics we just set h=c=1 and life gets sooo much better. 😎
Click to expand...

Didn't mean to seem badgering, by all means share whatever you like haha. It's funny, I actually like having an arsenal of discrete facts and terms at my disposal, it helps build my confidence I think.
 
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gettheleadout said:
Didn't mean to seem badgering, by all means share whatever you like haha. It's funny, I actually like having an arsenal of discrete facts and terms at my disposal, it helps build my confidence I think.
Click to expand...

Agreed. I think knowing most of the constants is good for confidence if nothing else. I happened to have many of them memorized simply from doing so many practice problems. It was never a conscious effort.
 
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