Phase changes and energy conservation

So you need to add the energy it takes to warm the water to the equilibrium temperature, using Q = mc(change in T). In summary, to find the equilibrium temperature of the cup and its contents, you need to set the energy gained from the ice cube equal to the energy lost by the water and the cup, taking into account the specific heat capacities of each substance and the phase change of the ice cube. Then, to find the equilibrium temperature with a silver cup, you would need to repeat this process using the appropriate specific heat capacity for silver.
  • #1
haquearsh
1
0

Homework Statement


A 35-g ice cube at 0.0 C is added to 110 g of water in a 62 g aluminum cup. The cup and the water have an initial temperature of 23 C.

a. Fine the equilibrium temperature of the cup and its contents

b. Suppose the aluminum cup is replaced with one of equal mass made from silver. Is the equilibrium temperature with the silver cup greater than, less than, or the same as with the aluminum cup? Explain.

Homework Equations


Q = mL
Q = mc(change in T)
cwater = 4186
cice = 2090
caluminum=900
Lice = 33.5 x 10^4

The Attempt at a Solution


]3. The Attempt at a Solution [/b]
I set the mL = [mwcw(Tfw-Tiw) + maca(Tfa - Tia)]
but that seems wrong, and there are another 20 steps after, so I'm going to not put that here
 
Physics news on Phys.org
  • #2
When you made the energy gained equal the energy lost, you only took into account the phase change from ice to water (Q = mL). After it has made the change, it is now water at 0 degrees, right?
 

FAQ: Phase changes and energy conservation

1. What is a phase change?

A phase change is a physical process in which a substance undergoes a transformation from one state of matter to another. This can include changes between solid, liquid, and gas states.

2. What is the role of energy in phase changes?

Energy is necessary for a phase change to occur. It is either absorbed or released during the change, and it determines the temperature and pressure at which the change takes place.

3. How does energy conservation apply to phase changes?

Energy conservation applies to phase changes because the total amount of energy in a closed system remains constant, even during a phase change. This means that the energy used to change the phase of a substance must come from or go into the surrounding environment.

4. What is the difference between endothermic and exothermic phase changes?

Endothermic phase changes absorb energy from the surrounding environment, causing a decrease in temperature. Examples of endothermic phase changes include melting and vaporization. Exothermic phase changes release energy into the surrounding environment, causing an increase in temperature. Examples of exothermic phase changes include freezing and condensation.

5. How do phase changes affect the properties of a substance?

Phase changes can alter the physical properties of a substance, such as density, melting point, and boiling point. These changes occur because the arrangement and movement of particles within the substance change as it undergoes a phase change.

Similar threads

Back
Top