Another homework thread. Thermodynamics help

WorthDaMoney

WorthDaMoney

Active member
so we're doing p-v (pressure vs specific volume) and T-v (temperature vs specific volume) graphs and im understanding it fine. but theres a question on my assignment that asks to draw the p-v and T-v graph of water when its p = 1 bar, and T = -12 celcius. from the temperature and pressure tables in the back of my book, it only shows temperatures over 0 celcius.

so my question is:

how do you draw a p-v graph for water at p = 1 bar and T = -12 celcius ?

+K for legit attempts to help
 
At 1 atmosphere, water will be frozen (solid) at 0 degree C......
that's probably why your chart only goes to o deg c.
 
not sure about your book but sometimes the temperatures are given in kelvin. if thats the case for you, change to kelvin and interpolate that shit.
 
its kind of obvious when someones a post whore . wasnt even close to a funny comment, and it didnt answer my question.

fuck off
 
no its given in celcius which is what i dont get because from what ive heard, they normally go to absolute zero.

and as for the other comment about it being solid, ive only learnt about p-v and T-v graphs for liquid, saturated vapour and superheated vapour. ill google a temperature table for solid ice

+K
 
I think as on a regular x and y axis graph, you would simply start the curve at p=1, V=0 instead of starting at (0,0). I've taken 3 chemistry classes and am currently taking Organic Chemistry, and I've never had to do this haha.
 
Dub post, but I just realized how dumb I am for saying what I just did because next semester I have a course entitled "Thermodynamics"
 
The only way you can use water in liquid state is to change the pressure at -12 degree c. Unless the water is seawater, aka brine. But sounds like a trick question - but don't quote me as i haven't seen any of your class work etc.
0 degree C = circa 273 k.
Have you learnt about PVT calculations etc? We do a lot of that in reservoir engineering and flow assurance.
 
YOU'RE THE FOOL MAKING A THREAD ON A SKIING WEBSITE ABOUT YOUR HOMEWORK, EVEN THOUGH YOU KNOW THERES ALREADY ABOUT 200 FROM THIS MONTH ALONE.

NOBODY IN NSG GIVES A SHIT ABOUT YOUR HOMEWORK, ASK YOUR MOM OR SOMETHING.
 
on the p-v T-v graphs we're making its to show that we have a general understand of how to plot both graphs with only the substance, and temperature and pressure values. the only specific values we plot are the values where the isobaric (sp) and bell curve intersect and at what point our substance is at on the graph.

you'll learn it next term, its fun !...
 
unlike you im actually learning something other than highschool art. so fuck off. get out of my thread. i clearly said in the title that it was a homework thread. if you dont want to read it, then dont. i dont want to have to respond to you again.

yes i mad.

i dont fucking like you awallace
 
Dear STEAMY-J.613's,I would be very surprised if you'd see temperature in Celsius in any equation or graph in chemistry. It sounds like youre dealing with the ideal gas law (PV=nRT). Have you tried to analyze your data after converting the temperature to Kelvin? You prolly know this but to convert it, just add 273.15 to the temperature in Celsius.
 
ya i know about changing the pressure to get different phase changing temperatures. if by PVT you mean pv = RT, then yes we have briefly and ive done it in highschool before too.if youre talking about the pvT graph, we have looked at those to see where the pv and Tv graphs come from, but only for that reason. i know there are sections for solid states on the pv and Tv graphs, i just dont know how to graph with a solid substance
 
How old are you and what level is this?
I'm an old engineer and have forgotten so much of this shit...school was a long time ago. ha.

 
im in second year mechanical . this is the second year thermo course. its really not that hard, but he hasnt gone over how to draw a solid substance on the pv Tv graphs. im pretty sure i can do it on the Tv graph because my pressure of 1 bar in on the table. so i draw my isobaric line at 99.63 celcius (from the table) and then plot my point on the compressed liquid side of the bell curve (now in the solid state i guess). the Tv plot is not a problem because it is at a constant pressure of 1 bar, but the pv graph must be at a constant temperature of -12, and there is no -12 celcius on my tables so i cant figure out where the isobaric line rests on the pv graph

hopefully that time it made sense
 
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