 #1
 16
 2
 Homework Statement:
 Ice cubes of total mass 150 g are placed in a vacuum flask holding 350 g of water at a temperature of 80 degrees Celsius. Assuming the vacuum flask loses no heat and has negligible heat capacity, what will be the final temperature of the water after all the ice has melted.
 Relevant Equations:

Q = mLf,
Q = mcΔT
First, I calculated the heat required for the ice to melt:
Q=mLf
Q=0.150×330
Q=49.5 J
Then, I calculated the final temperature of the water by forming the following equation:
Q=mcΔT
−49.5=(0.15+0.35)×4200×(Tf −80)
Tf=80.0 degrees Celcius
But the answer says 32 degrees Celsius.
Q=mLf
Q=0.150×330
Q=49.5 J
Then, I calculated the final temperature of the water by forming the following equation:
Q=mcΔT
−49.5=(0.15+0.35)×4200×(Tf −80)
Tf=80.0 degrees Celcius
But the answer says 32 degrees Celsius.