ICY HOT LAB 2014

Purpose: to observe the temperature changes as water changes phase.

In your lab NB, complete the followingPrelab questions:

  1. Sketch the lab set-up.
  2. What is the “system” that you will be observing?
  3. How will energy be added to the system (Q, W or R)? How do you know this?
  4. Identify the independent variable and the dependent variable in the lab.
  5. Make a prediction of how temperature will change as water changes from a solid to a liquid to a gas. Make a sketch as part of your prediction.
  6. Make a particle diagram of each phase of water…solid, liquid and gas. Draw arrows between the phases and label with the following: condensation, vaporization, solidification, melting, sublimation, deposition.
  7. Make a data table to record temperature of water every 30 secs.

Materials:

250 mL beakertap waterice cubesgraduated cylinder

Stirring rodhot platethermometer

Procedures:

  1. DO NOT START HEATING HOT PLATE UNTIL STEP 6.
  2. Select your glassware and clean it. Be sure to dry it completely.
  3. Measure 30 mL of tap water and add to your 250 mL beaker.
  4. Add approximately 100 mL of ice to your beaker. Allow beaker to sit for 2 minutes.
  5. Place the beaker on the hot plate and record the initial temperature.
  6. Plug the hot plate in, set at a medium temperature level and constantly stir the water and ice throughout the experiment.
  7. Record the temperature every 30 seconds and record this information in the data table.
  8. Record all qualitative and quantitative observations of the melting ice. (Question guide on back of page)
  9. Record the temperature and the time when the all of the ice has completely melted. This is a very important data point on your graph.
  10. Keep recording the temperature until all of the water is boiling; be sure to record the exact temperature and time when all of the water in your beaker is boiling. This is a very important data point on your graph.
  11. Continue recording the temperature until the water has been boiling for THREE minutes.
  12. Unplug the hot plate and allow the beaker and water to cool. Then pour the contents down the drain. Be careful not to burn yourself.
  13. Dry off your supplies and return them to cart.

Icy-Hot Lab Question Guide: Record in lab NB.

  1. As you heat the beaker with a gentle flame, what is happening to the temperature of the system. How do you know?
  1. What phases are present in the beaker?
  1. Draw particle diagrams for particle level changes occurring as the ice melts.

Ice and a little water
Temperature =
Time = / Half ice and half water
Temperature =
Time = / All water
Temperature =
Time =
  1. What happens to the kinetic energy of the system as the ice is melting? How do you know?
  1. When all the ice has melted, what happens to the temperature of the system?
  1. What phase(s) is (are) present in the beaker at this time?
  1. Draw particle diagrams for particle level changes occurring as the water heats up.

Ice just melted
Temperature =
Time = / Water at room temperature
Temperature =
Time = / Hot water
Temperature =
Time =
  1. What happens to the kinetic energy of the system as the water continues to heat? How do you know?
  1. When the water starts to boil, what happens to the temperature of the system?
  1. What phase(s) is (are) present in the beaker at this time?
  1. Draw particle diagrams for particle level changes occurring as the water boils.

Water just starts boiling
Temperature =
Time = / Water boiling
Temperature =
Time = / Some water boiled away
Temperature =
Time =
  1. What happens to the kinetic energy of the system as the water is boiling? How do you know?