Solution to Thermo Ice Melting Problem

Click For Summary
SUMMARY

The discussion centers on solving the Thermo Ice Melting Problem involving an insulated beaker containing 0.325 kg of water at 69.9°C and determining the mass of ice at -15.0°C needed to achieve a final temperature of 39.0°C. The specific heats of water and ice are given as 4190 J/(kg·°C) and 2100 J/(kg·°C), respectively, with the heat of fusion for ice being 334,000 J/kg. The calculated mass of ice required is 0.2155 kg, but participants noted the importance of including the energy needed to melt the ice in their calculations.

PREREQUISITES
  • Understanding of thermodynamics principles, specifically heat transfer.
  • Familiarity with specific heat capacity calculations.
  • Knowledge of the heat of fusion for phase changes.
  • Ability to solve algebraic equations involving multiple variables.
NEXT STEPS
  • Review the concept of heat transfer in thermodynamic systems.
  • Study the calculations involving specific heat and heat of fusion in detail.
  • Learn how to set up and solve energy balance equations in thermal problems.
  • Explore practical applications of thermodynamics in real-world scenarios.
USEFUL FOR

Students studying thermodynamics, physics enthusiasts, and educators looking for practical examples of heat transfer and phase change calculations.

mysticjbyrd
Messages
18
Reaction score
0

Homework Statement


An insulated beaker with negligible mass contains liquid water with a mass of 0.325 \rm{kg} and a temperature of 69.9 C.

How much ice at a temperature of -15.0 C must be dropped into the water so that the final temperature of the system will be 39.0 C?
Take the specific heat of liquid water to be 4190 , the specific heat of ice to be 2100 , and the heat of fusion for water to be 334

Homework Equations


Q = mcT
Q = mL

The Attempt at a Solution


m = mass of ice

Melt Ice = 334 * m
Heat Ice = 2100 * (0--15) * m
Heat ice water = m*4190 * (39-0)

Cool Water = 0.325 * 4190 (39-69.9) = 42078.075

Solve for m
42078.075 = 334 * m + 2100 * (0--15) * m + m*4190 * (39-0)

m= 0.2155 kgFound another equation and used it and got the same answer... not sure where I am going wrong.

Mice = Mwater * Cwater (Tf - Twater)/(Cice * Tice -Lf - Cwater * Tf)

[0.325 * 4190 * (39-69.9)] / (2100 * -15 -334-4190*39) =0.2155kg
 
Last edited:
Physics news on Phys.org
Anyone got an idea what's up? When I plugged in the answer it told me "Dont forget the energy needed to melt the ice. ?
 
The heat of fusion if Ice is actually 334 KJ/kg or 334*10^3 J/kg
 

Similar threads

Replies
4
Views
2K
Replies
12
Views
1K
Replies
11
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 14 ·
Replies
14
Views
2K
  • · Replies 17 ·
Replies
17
Views
6K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 8 ·
Replies
8
Views
3K