Homework Statement
A well-fitting piston with 4 small holes in a sealed water-filled cylinder,shown in Fig is pushed to the right at a constant speed of 4 mm /s while the pressure in the right compartment remains constant at 50 kPa gage. Disregarding the frictional effects,determine the force...
We couldn't calculate the internal energy of a substance directly and we define it as change of state so we differentiate equation U=Q-PV and obtain dU=dQ-PdV and then integrating it as a result we get ΔU=ΔQ-PΔV.
Homework Statement
I was trying to obtain Tds=dh-Vdp by differentiating the internal energy equation U=Q-PV and doing some arrangements but at the end I couldn't achieve my goal.The part that I don't understand is when we differentiate H=U+PV we obtain dH=dU + PdV + VdP and then from there we...
We should multiply entropy by the number of moles of each liquid before finding the net entropy of the system.Thus,
If we mix 1 mole of liquid water at 0°C with 2 mole of liquid water at 100°C so the result should be:
ΔS=1x3.02 cal/deg= 3.02 cal/deg
ΔS=2×(-2.59 cal/deg)= -5.18 cal/deg...
ΔS=-2.59 X 1/2 cal/deg mol =-1.295
ΔS= 3.02 X 1/2 cal/deg mol =1.51
ΔS°=1.51-1.295=0.215 cal/deg mol I think this is the correct answer now.Is there any mistake in the unit of ΔS° ?
What if we mix 1 mole of liquid water at 0°C with 2 mole of liquid water at 100°C.How will the result change?
Because in this equation ΔS=∫dQ/T entropy doesn't depend on quantity of substance.So can we say entropy doesn't depend on mole of the substance for the whole concept?
Step 1: Heat Loss=Heat Gain
m.Cwater.ΔT1=m.Cwater.ΔT2 (Moles are equal so the mass)
(100°C-T)=(T-0°C)
T=50°C
Step 2: Calculations for 0.5 mole liquid water at 100°C
Ti=100°C----> 100 +273.3=373.3°K
Tf=50°C------> 50+273.3=323.3°K
ΔS=∫dQ/T pressure is constant therefore ΔS=∫CpdT/T from 373.3°K...
Homework Statement
Calculate the ΔS° when 0.5 mole of liquid water at 0°C is mixed with 0.5 mole of liquid water at 100°C.Assume Cp=18cal/deg mole over the whole range of temperatures.
Homework Equations
ΔS=∫ Cp/T dT