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Please help me ASAP! prelim chem help (1 Viewer)

turntaker

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I basically suck at chemistry because I didn't study constantly this year. Can someone please explain to me what these formulas mean/do. My exam is in the morning.
uploadfromtaptalk1410358604113.jpg
 

madharris

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n=m/M
number of moles = mass/Molar mass

^H=-mC^T
H = heat energy
m= mass
c = specific heat (usually water I think? which is like 4.186 iirc)
delta t = change in temperature (= final - initial temp)

c=n/v
c = concentration
n = number of moles
v = volume

C1V1=C2V2
C1 = Concentration 1
C2 = Concentration 2
V1 = Volume 1
V2 = volume 2

What I usually did when I was lost was write out what I had from the information

e.g. if a question was asking me to find the mass of something.
then in the question I might have a c, and might have had a v.
Then I would figure out which equations this would fit in, so I would calculate an n once I figured that out.
Then I would look, what equation also has an n and has m? and that would be n=m/M
So I would figure out M, rearrange the equation and calculate.

Wow that probably made no sense.. sorry. hahaha. I'm procrastinating from my own study :p
 

turntaker

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Thanks guys I failed pretty bad anyway
 

someth1ng

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Chemistry isn't one of those subjects where you can completely forget year 11 content, you should revise it during the holidays.
 

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