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09-09-2002, 01:36 PM
Okay here is a chemistry problem that I have done, I wanted to check it with other people...btw this stuff is really hard to me so don't be too critical...

The problem:
there are 6.02E23 atoms of mercury in 201g of mercury, the density of mercury is 13.5g/mL. What is the volume of the same liquid, in micro m3, occupied by one atom of mercury?

My final solution:
One atom takes up:
2.45E-23 mL

How I solved it:
If 201g of mercury has 6.02E23 atoms, then 13.5g of mercury must have 6.02E23 / (201/13.5)
NumberOfAtoms = 6.02E23 / (201/13.5)
NumberOfAtoms = NumberOfAtoms * (1mL / NumberOfAtoms)

Do you think I'm correct? Chemistry sucks

Govtcheez
09-09-2002, 01:42 PM
That's what I got, too... This really isn't chemistry - it's just math...

09-09-2002, 02:46 PM
Thank you for 1) Posting 2) Backing up my answer :)
I agree that it's just math. I'm supposed to be using factor labeling, I don't know if you know what that is...it's just a way of setting up your conversions. Well anyway I didn't use factor labeling, I just did it like I would any other normal math problem. Anyways I don't even know how to set up this problem using factor labeling. I have another chemistry problem I'd like to check sometime later, and it actually has some factor labeling involved, but liek it's converting mm to cm... 1mm = .1cm...it's easy stuff, the rest I did without factor labeling

09-09-2002, 02:54 PM
If a frying pan needs a Teflon coating that is 1.0mm thick, and the area covered is 36 square inches, how many pounds of teflon are required to coat the pan?
teflon has a density of .805g/cm3

My solution:
1.34E-2lbs

How I got it:
First I found the volume of the teflon in cm3
Volume = 1mm(36inches)
Volume = .1cm(2.54 * 36)^2 //2.56cm = 1inch
Volume = 8.36E2cm^3
//Now I find the total mass in grams then convert it to pounds
//the density of teflon is .805 g for every cm3
Total mass in grams = .805 * Volume
Total mass in grams = .805 * 8.36E2cm^3
Total mass in grams = 6.72E2g

//Now convert to lbs, 1g = .002lb
6.72E2 (.002) = 1.32E-2lbs

If anyone could either back me up of help explain to me why it is wrong I would be very happy.

I am always thinking of ways to incorporate a C++ program into homework so if you have any cool ideas that a program could do I'm all ears.

Magos
09-09-2002, 02:57 PM
:eek: :confused:
The first time I've seen a triple posting...!!!
<Dark Voice>Shame on you!</Dark Voice> :)

09-09-2002, 03:03 PM
Yes I know, actually quadruple posting if you want more shock value, and also I found a BLATANTLY GLARING problem with what i did before...I'm fixing it right now...

09-09-2002, 03:19 PM
Okay the actual answer is 3.7E-2, how I got there isn't important because I don't need help anymore...I confirmed the answer with a friend on the phone and she said it's correct so thanks if you were going to helpme anyways

MethodMan
09-09-2002, 05:18 PM
Am I glad I never took chemistry, although that did close the door on me going into engineering.

endo
09-10-2002, 07:59 AM
OMG, this has illustrated how much I've forgotten since I did my chemistry degree!!! :(

Clyde
09-10-2002, 04:01 PM
you did a chemistry degree and you struggled with that?

BMJ
09-10-2002, 04:07 PM
lol :D