Molar Enthalpy of Fusion for Ice

One goal is to understand _____ for calculations

Heating and cooling curve

Another goal is to understand the __ of molar enthalpy

definition

As you move from the solid to the liquid to the gas form, what must happen?

heat must be absorbed from the environment

As you move from the gas to the liquid to the solid form, what must happen?

Heat must be released to the environment

What is Deposition?

when a substance goes directly from gas to solid

What is sublimation?

when a substance goes directly from solid to gas

What is the molar enthalpy of fusion?

amount of energy needed to melt 1 mole of ice

What is the molar enthalpy of fusion equation?

Q = nΔHfusion

What is n =?

moles of ice

What is ΔH?

enthalpy change (J/mol)

Enthalpy =

heat divided by the number of moles

What equation should be used for 3 different phases in the Heating Curve?

Q = mcΔT

In Q = mCΔT, what is m?

mass

In Q = mcΔT, what is c?

specific heat

Does the specific heat of ice, water, and water vapor all defer from eachother?

yes

What equation should be used for melting on the heating curve?

Q = nΔHfusion

What equation should be used for vaporization on the heating curve?

Q = nΔHvaporization

You must use the specific heat of ice in the equation until the temp reaches:

0 degrees C (freezing temp of water)

You must use the specific heat of water in the equation until the temp reaches:

100 degrees C (boiling temp of water)

You must use the specific heat of water vapor in the equation if the temp:

is more than 100 degrees C

When we add ice to hot water in the lab, what will we measure and what will we use?

Coffee Cup Calorimeter & the heat exchange between the water and ice

How do you add the substance to the calorimeter?

push the side of the inverted cup to create an opening

Fill 600ml beaker with:

deionized water

Warm DI water to?

70-75 degrees C

What should you do after adding the ice?

weigh the paper towel

Work __ after ice is added

quickly

Specific heat of ice?

2.09 J/g°C

Specific heat of water?

4.18 J/g°C

Specific heat of water vapor/steam?

1.86 J/g°C