## van der waals problem

## van der waals problem

(OP)

hello i am new at this and i cant solve van der waals equation

on mathcad

i tried R:=0.0821 Latm\mol K

P:=1,2...3 atm T:=283,287...333 K a:=3.59 b:=0.0427

and write the equation

f(V):=[(P+(a/V^2))*(V-b)]-[R*T]

now what should i do to get volume values from this equation

i tried everything i couldnt find some examples similar

plz help on it

thanks for helps

on mathcad

i tried R:=0.0821 Latm\mol K

P:=1,2...3 atm T:=283,287...333 K a:=3.59 b:=0.0427

and write the equation

f(V):=[(P+(a/V^2))*(V-b)]-[R*T]

now what should i do to get volume values from this equation

i tried everything i couldnt find some examples similar

plz help on it

thanks for helps

## RE: van der waals problem

TTFN

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## RE: van der waals problem

ihave pressure, temparature ,R ,a,b

i defined all i have 3 diffent pressure value

and 10 diffrent temp value (it means 30 diffrent volume values)i want to find them with van der waals

if i had have volume values i could easly found temperature

or pressure parameters but when volume is variable , it

is more complex

i think it can be solved by given-root

but i don know how

## RE: van der waals problem

[P+(a/v^2)]*(V-b)=R*T

i need to find volume by use this

sorry about my poor english

## RE: van der waals problem

Given

[P+(a/v^2)]*(V-b)<CTRL>=R*T

func(P,T):find(V)

i:1;10 j:1;3

func(P

_{j},T_{i})=TTFN

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## RE: van der waals problem

says func isnt defined

## RE: van der waals problem

TTFN

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## RE: van der waals problem

## RE: van der waals problem

TTFN

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## RE: van der waals problem

## RE: van der waals problem

You need to supply a guess value for V. You futher compound whatever other problems you might have by not using units, but also using V, which is a built-in unit designating volts.

TTFN

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## RE: van der waals problem

but when i want to find P:=1,2..3 it say

this value must be scalar or matris

my problem is finding V for different P and T (indices)

look at new worksheets

## RE: van der waals problem

## RE: van der waals problem

i have no idea about vectors and matrises on mathcad

but it will help me to understand

and problem is solved

thanks and thanks again

## RE: van der waals problem

TTFN

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## RE: van der waals problem