Heat of Transformation: Does It Affect Temperature?

In summary, the energy goes into breaking the bonds between water molecules, which changes its temperature from 0*C to 6*C.
  • #1
1MileCrash
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What happens to the heat required in heat of transformation?

It doesn't actually raise the temperature of the substance does it?

IE if I have ice at 0*C and I input the exact energy required to melt it, it's still 0*C?
 
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  • #2
To my knowledge the temperature stays the same while the material undergoes a phase change.
 
  • #3
It goes into the lattice.

Temperature is a statistic of microscopic particles, it doesn't mean energy.
 
  • #4
I agree that temperature isn't energy, but I'm talking about the energy required for the phase-change. Seeing that the addition of energy does imply a change in temperature until the melting point in which it goes into the required heat of transformation, I wondered where it "actually" went.

But I think I understand your answer, energy will raise the temperature until a certain point, but additional energy is then required to break the molecular lattice. Correct?
 
  • #5
Ye correct.
 
  • #6
And the same energy is stored as potential energy until the object freezes again and reforms the lattice, releasing that energy as heat again?

Thanks, this will let me do problems like this more confidently.
 
  • #7
For example (this is a homework problem but it is merely to demonstrate)

Fifty grams of ice at 0°C is placed in a thermos bottle containing one hundred grams of water at 6°C. How many grams of ice will melt? The heat of fusion of water is 333 kJ/kg and the specific heat is 4190 J/kg


After all of that happens, equilibrium pressure is still just 0*, because all the energy the *6 water went into breaking (a fraction of) the ice's lattice?
 
  • #8
The energy that goes into turning ice at 0°C into water at 0°C goes into breaking the bonds between the water molecules that form the ice. Temperature is energy. It's the product of the kinetic energy of the particles.
 
  • #9
yes. the energy added is used only to change its phase from solid to liquid but not used to raise its temperature from 0*C. Same thing goes when you vaporize water at let's say 110*C, you add heat to change its phase from liquid to gas at constant temperature. :)
 

What is the heat of transformation?

The heat of transformation, also known as the enthalpy of transformation, is the amount of energy required for a substance to change from one state to another (e.g. solid to liquid or liquid to gas) at a constant temperature. It is a measure of the strength of the intermolecular forces between particles in a substance.

How does the heat of transformation affect temperature?

The heat of transformation does not directly affect temperature. Instead, it is a measure of the energy required to change the state of a substance at a specific temperature. When a substance is undergoing a phase change, such as melting or boiling, the heat of transformation is absorbed or released, causing a change in the particles' kinetic energy and resulting in a change in temperature.

What factors can affect the heat of transformation?

The heat of transformation is dependent on several factors, including the type of substance, the amount of substance undergoing the phase change, and the external pressure. Additionally, the heat of transformation is affected by the initial and final temperatures of the substance, as well as any external heat sources or sinks.

Can the heat of transformation be negative?

Yes, the heat of transformation can be negative. This occurs when a substance is undergoing a phase change in the opposite direction, such as when a gas is condensing into a liquid or a liquid is freezing into a solid. In these cases, the heat of transformation is released, resulting in a decrease in the substance's temperature.

How is the heat of transformation measured?

The heat of transformation is typically measured using calorimetry, which involves using a calorimeter to measure the amount of heat absorbed or released during a phase change. It can also be calculated using the equation Q = m x L, where Q is the heat of transformation, m is the mass of the substance, and L is the specific latent heat of the substance.

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