Phase Changes - Lab Follow-up

Phase Changes - Lab Follow-up

Think. . .

What do you think happens to the temperature of a material while it is melting or boiling (phases changes)?

A. The temperature decreases during a phase change.

B. The temperature remains the same during a phase change.

C. The temperature increases during a phase change.

Multiple Choice

Based on the video, what is happening at C?

• Ice is warming up.

• Liquid water is warming up.

• Water vapor is warming up.

• Ice is changing to liquid water.

• Liquid water is changing to water vapor.

Multiple Choice

Based on the video, what is happening at B?

• Ice is warming up.

• Liquid water is warming up.

• Water vapor is warming up.

• Ice is changing to liquid water.

• Liquid water is changing to water vapor.

Use this graph to determine the melting point and boiling point of this material (next two questions).

Multiple Choice

According to this graph, what is the boiling point for this material?

• 70 ^oC

• 45 ^oC

• 25 ^oC

• 10 ^oC

• -10 ^oC

Multiple Choice

According to this graph, what is the melting point for this material?

• 70 ^oC

• 45 ^oC

• 25 ^oC

• 10 ^oC

• -10 ^oC

_{Phase Change Lab - Data}

• This is data from the phase change lab.

• This data was taken as liquid water began to boil (it doesn't show the entire heating curve).

• Think about what you can learn from this graph.

• Blue = water; Green = salt water; Black = alcohol

• 
  

• 
  

Think About This. . .

• Why is part of the graph sloped, but part of the graph is flat?

• Why does the graph for alcohol look so different from the others?

• In which part of the graph are the materials boiling?

• What physical property of these materials can you determine from this graph?

• 
  

• 
  

Multiple Choice

What happens to the temperature of a material while it is melting or boiling (phases changes)?

• The temperature decreases during a phase change.

• The temperature increases during a phase change.

• The temperature remains constant during a phase change.

Multiple Choice

What is happening during the sloped part of the graph?

• The temperature is INCREASING; the water IS NOT boiling.

• The temperature is INCREASING; the water IS boiling.

• The temperature is CONSTANT; the water IS NOT boiling.

• The temperature is CONSTANT; the water IS boiling.

Multiple Choice

What is happening during the flat part of the graph?

• The temperature is INCREASING; the water IS NOT boiling.

• The temperature is INCREASING; the water IS boiling.

• The temperature is CONSTANT; the water IS NOT boiling.

• The temperature is CONSTANT; the water IS boiling.

Multiple Choice

Why does the graph for alcohol look so different from the water and salt water graphs?

• Alcohol has a lower melting point than the other materials.

• Alcohol has a lower boiling point than the other materials.

• Alcohol heats up faster than the other materials.

• Alcohol heats up slower than the other materials.

Multiple Choice

Which material has the highest boiling point?

• Alcohol

• Water

• Salt water

• Impossible to tell

Multiple Select

Which of these can NEVER happen? [Select all that apply.]

• Boiling water gets hotter.

• Melting ice gets warmer.

• Solid ice gets warmer.

• Liquid water gets warmer.

Hope you learned something!