Help! for Chemistry H.W.
posted by Lori .
I need help with my chem home work. Please show me the answers because this question is a very confusing question to me. Therefore I really need you to provide the answer to this question please...
Question 1:
A sample of CO2 gas with a mass of 0.30 g is placed in a 250 mL container at 400 K. What is the pressure in atmospheres exerted by this gas?
I would like you to know that before you put the numbers into an equation and solve for the volume, you would have to change the mass to moles by using the following correct equation and only choose one that is correct that was provided in my home work. The following equations are:
Mass* molar mass, mass/molar mass, mass* (6.02 x 10^{23}), and mass/(6.02 x 10^{23}).
I also would like to let you know that when you calculate the molar mass of CO2. What answer do you get?
After you get the answer you would need to round the atomic masses to the hundredths place and your answer should also be rounded to the hundredths place.
Also after that you need to use the equation you chose above to calculate the moles of CO2 and round to the ten thousandths place and you will get an answer also.
Then you will need to convert the answer you got and convert the mL to L.
For example this example is provided in my homework it is:
250 x one of these answers 1000L/mL, 1L/1000mL,100L/mL and 1L/100mL. One of the correct answer above must be chosen. And the answer would have to = the answer in L.
After you are done you will need to plug in the your data into the correct ideal gas law equation and you will get an answer. And after that you will then round to the hundredths place.
That all. I really hope you can help me with this question because it is on my home work, but I try to answer it so many times that I just gave up because I didn't even seem to be getting the correct answer and I also had a big headeake. Please provide me with the answers because I feel like I can take it anymore, too confusing for me.

Giving you the answer doesn't cure the problem. The problem is that you don't know how to work the homework problem and you need to learn how. I saw this problem yesterday and most of the directions were provided by the teacher (at least that's what I was told). Here is the equation you need to use. If you will follow the instructions you should come up with the answer you need. If you have trouble with any part, post that part as a separate post, tell what instructions the instructor has given, and tell us what you don't understand about that question. I can help you through it but I don't want to do your homework for you. The equation you need is
PV = nRT
P is in atmospheres, V is in liters (the 250 mL = 0.250 L), n is number of mols (#mols = grams/molar mass), R is the general gas constant of 0.08206 L*atm/mol*K, and T is temperature in Kelvin (C + 273). 
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