Determine the final temperature of the mixture

Click For Summary
SUMMARY

The discussion focuses on calculating the final temperature of a mixture consisting of 21.4 grams of ice at 0.0°C and 13.1 grams of steam at 100.0°C in a sealed container. The relevant equations include Q=mcΔT and Q=mL, with latent heat values of 334 kJ/kg for fusion and 2257 kJ/kg for vaporization. The solution involves recognizing that the energy required to melt the ice is less than the energy required to condense the steam, leading to a scenario where the steam condenses before all ice melts. The final temperature is determined after accounting for the energy transfer between the two phases of water.

PREREQUISITES
  • Understanding of thermodynamics principles, specifically heat transfer.
  • Familiarity with phase changes and latent heat concepts.
  • Proficiency in using the equations Q=mcΔT and Q=mL.
  • Basic knowledge of the properties of water at different states (ice, liquid, steam).
NEXT STEPS
  • Study the concept of latent heat in detail, focusing on practical applications.
  • Learn how to apply the principle of conservation of energy in thermodynamic systems.
  • Explore problems involving mixed-phase systems and their equilibrium states.
  • Investigate the specific heat capacities of water in different states for more complex calculations.
USEFUL FOR

Students studying thermodynamics, physics educators, and anyone interested in solving heat transfer problems involving phase changes in water.

Stomper123
Messages
6
Reaction score
0

Homework Statement


A student places 21.4 grams of ice at 0.0C and 13.1 grams of steam at 100.0C in a sealed and insulated container. Determine the final temperature of the mixture.
m(ice)= 21.4 g or 0.0214 kg
m(steam)= 13.1 g or 0.0131 kg
Ti(ice)= 278.15 K
Ti(steam)= 378.15 K
Tf(ice)=Tf(steam)
Latent heat of fusion: 334 kJ/Kg
Latent heat of vaporization 2257 kJ/kg

Homework Equations


Q=mcΔT
Q=mL
Qt(hot)= -Qt(cold)

The Attempt at a Solution


I did it on paper and attempted to solve for T2 using latent heat of fusion on one side and the vaporisation on the other side but ended up getting 57.74K which I know is impossible. I think one of the objects doesn't fully change state but I don't know how to do those kinds of problems.
 
Physics news on Phys.org
I think what you can do is look at the difference between the energy required to melt that amount of ice, and the energy required to condense that amount of steam. The former is less than the latter. Once enough energy has been transferred to melt all of the ice, the steam is still condensing, and the balance/remainder is used to heat that 0.0 C liquid water. Once the condensing is finished, you'll have some newly condensed water at just under 100 C, and some other liquid water at some temperature that depends on how much heating took place after melting (which depends on this difference/balance/remainder of energy I referred to in bold above). Now you can just use Q = mc delta T to find the final equilibrium temperature from this starting point of two amounts of liquid water at two different temperatures.
 
Check your absolute temperature values. I think you will find them to be slightly off.
 

Similar threads

Replies
12
Views
1K
  • · Replies 5 ·
Replies
5
Views
6K
  • · Replies 5 ·
Replies
5
Views
5K
Replies
7
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 11 ·
Replies
11
Views
5K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
6K
Replies
6
Views
6K