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Alwahsh
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A Question about the "General Gas Law" (PV/T)=nR
The general gas law states that : PV/T = nR
where P is the pressure of the gas , V is the volume of the gas and T is the absolute temperature in Kelvin scale , n is the number of moles and R is the universal gas constant
My question is not really a problem but I can't understand something in the proof .
since PV/T = nR
therefore (P1V1/T1) = (P2V2/T2) We can say V1 = Density/Mass
therefore (P1M/Density1T1) = (P2M/Density2T2) At Constant Mass
therefore (P1/Density1T1) = (P2/Density2T2)
then this rule is taken to say :
Density = Mass/Volume
-At Constant Mass we say : (P1V1/T1) = (P2V2/T2) we exchanged density by Mass/volume and canceled the mass as it is constant .
-At Constant Volume we say : (P1/M1T1) = (P2/M2T2) we exchanged density by Mass/Volume and canceled the volume as it is constant .
My question is here , when the mass is changed , how can we use this rule although we said at the beginning of it "At Constant Mass" and where did the Mass that was in the very first rule go ??
I hope I've made myself clear .
Thanks
Homework Statement
The general gas law states that : PV/T = nR
where P is the pressure of the gas , V is the volume of the gas and T is the absolute temperature in Kelvin scale , n is the number of moles and R is the universal gas constant
My question is not really a problem but I can't understand something in the proof .
since PV/T = nR
therefore (P1V1/T1) = (P2V2/T2) We can say V1 = Density/Mass
therefore (P1M/Density1T1) = (P2M/Density2T2) At Constant Mass
therefore (P1/Density1T1) = (P2/Density2T2)
then this rule is taken to say :
Density = Mass/Volume
-At Constant Mass we say : (P1V1/T1) = (P2V2/T2) we exchanged density by Mass/volume and canceled the mass as it is constant .
-At Constant Volume we say : (P1/M1T1) = (P2/M2T2) we exchanged density by Mass/Volume and canceled the volume as it is constant .
My question is here , when the mass is changed , how can we use this rule although we said at the beginning of it "At Constant Mass" and where did the Mass that was in the very first rule go ??
I hope I've made myself clear .
Thanks