What Determines Equilibrium in a Liquid-Vapor System?

  • Thread starter Thread starter erisedk
  • Start date Start date
  • Tags Tags
    Equilibrium
AI Thread Summary
In a liquid-vapor system at equilibrium, the molecules in both phases have equal total energy, which encompasses both potential and kinetic energy. The discussion clarifies that intermolecular forces are stronger in liquids than in gases, ruling out option (A). The confusion lies between potential energy (PE) and total energy (TE), with a focus on how kinetic energy (KE) relates to temperature. It is noted that KE is not the determining factor at equilibrium, as it is proportional to temperature, which varies between phases. Ultimately, the consensus is that total energy is the key factor in determining equilibrium.
erisedk
Messages
372
Reaction score
7

Homework Statement


A liquid is in equilibrium with its vapor at its boiling point. On an average, the molecules in the two phases have equal:
(A) inter-molecular forces
(B) potential energy
(C) total energy
(D) kinetic energy

Homework Equations

The Attempt at a Solution


I know (A) is wrong as intermolecular forces in liquids are much more than those in gases. However, I'm confused between (B) (C) and (D). I know in gases KE is directly proportional to temperature. I'm not really sure about anything beyond this.
 
Physics news on Phys.org
Okay --- it's not KE. That leaves PE and TE; do you think TE might be related more to KE than PE? Or, less?
 
Why isn't it KE? Shouldn't KE also be proportional to temperature in liquids?
And I don't know whether TE might be more related to KE or PE.
 

Thread 'Struggling to understand the concept of this question (ice cube in water optics question)'

TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
View full post »
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
View full post »

Similar threads

I Is equilibrium vapor pressure different in vacuum and in air?
Replies
2
Views
2K
Study of harmonic motion of a liquid in a V shaped tube
Replies
2
Views
1K
Possible webpage title: How Does Condensing Water Improve Furnace Efficiency?
Replies
1
Views
1K
Vapor Pressure vs Atmospheric Pressure
Replies
2
Views
8K
Two monatomic ideal gases are in thermal equilibrium with ea
Replies
8
Views
6K
Potential energy in solids,liquids and gases
Replies
4
Views
3K
What is the temperature of equilibrium when mixing ice and vapor?
Replies
9
Views
1K
How Does Intermolecular Potential Energy Behave in Ideal and Real Gases?
Replies
2
Views
5K
Particle Model of Thermal Energy questions
Replies
1
Views
3K
Does pressure affect equilibrium vapor pressure (or RH)?
Replies
8
Views
3K

Hot Threads

Recent Insights

Back
Top