h20 phase change lab
Background H2O, or more commonly know as water, is one of the most common materials on Earth. We interact with it every day: it the air around us, in puddles on the ground, and even within ourselves. We also know that H2O is commonly found in all three of the different forms of matter: ice as the solid, water as the liquid, and steam as the gas. We know that we can quickly change between the different forms of H2O by either increasing or decreasing temperature. We have worked with hot plates and thermometers in other labs before, so we know how to be safe. I wonder what a graph of the changing temperatures over time between the phases would look like.
Hypothesis Based on prior learning, I predict that the graph of the water phase changes will not be one straight slope, but instead will plateau, or be flat, and then slope between the change of ice to water, plateau and slope once more between the change of water to steam, and then plateau once more. If we record the temperature of the H2O at regular intervals, then we will be able to make the predicted graph.
Procedure
· List of Materials: 1 thermometer (0 to 100 °C), 1 beaker (250 or 400 mL), 1 hot plate, ice (enough to fill the beaker), tap water (about 25 mL), 1 graduated cylinder (optional), safety goggles, lab apron, at least 1 rag (to clean up spills), pencil/pen, notebook/paper, graph paper, and access to an electrical outlet.
· Steps:
1. Prepare a data table to collect measurements from the lab. Make sure to put the dependent and independent variables in the correct place.
2. Fill the beaker with ice and add a small amount of water (about 25 mL)
3. Place the beaker on the hot plate with the hot plate TURNED OFF.
4. Take two temperature measurements of the ice/water slurry 30 seconds apart.
5. Do not let go of the thermometer.
6. Do not let the thermometer touch the beaker’s sides or bottom.
7. Turn the hot plate on to about 6 (about halfway).
8. Collect temperature measurements every 30
Hypothesis Based on prior learning, I predict that the graph of the water phase changes will not be one straight slope, but instead will plateau, or be flat, and then slope between the change of ice to water, plateau and slope once more between the change of water to steam, and then plateau once more. If we record the temperature of the H2O at regular intervals, then we will be able to make the predicted graph.
Procedure
· List of Materials: 1 thermometer (0 to 100 °C), 1 beaker (250 or 400 mL), 1 hot plate, ice (enough to fill the beaker), tap water (about 25 mL), 1 graduated cylinder (optional), safety goggles, lab apron, at least 1 rag (to clean up spills), pencil/pen, notebook/paper, graph paper, and access to an electrical outlet.
· Steps:
1. Prepare a data table to collect measurements from the lab. Make sure to put the dependent and independent variables in the correct place.
2. Fill the beaker with ice and add a small amount of water (about 25 mL)
3. Place the beaker on the hot plate with the hot plate TURNED OFF.
4. Take two temperature measurements of the ice/water slurry 30 seconds apart.
5. Do not let go of the thermometer.
6. Do not let the thermometer touch the beaker’s sides or bottom.
7. Turn the hot plate on to about 6 (about halfway).
8. Collect temperature measurements every 30