Activity Title: Phase Changes Using Scratch

Activity Title: “Phase Changes Using Scratch”

Summary:

Using an existing Scratch simulation, students will identify different types of phase changes when prompted by questions that will guide them through different phase change processes. Students will answer the questions based on the demos and their prior knowledge.

Procedure

Background:

First, you need to review your notes on phase change. You should be familiar with the following vocabulary terms: phase change, melting, freezing, condensation, evaporation, sublimation, deposition, solid, liquid, and gas.

Preparation:

-Use a browser to open this web site:

Lab Activity:

1. Follow the instructions on the right side of the screen as they appear.
2. Make the simulation full screen by clicking the full screen button on the top left side.
3. Click the green flag and begin!
4. Complete the following worksheet as you go through the review.

Phase Change Review Worksheet

The graph was drawn from data collected as a substance was heated at a constant rate. Use the graph to answer the following questions.

At point A, the beginning of observations, the substance exists in a solid state. Material in this phase has ______volume and ______shape. With each passing minute, ______is added to the substance. This causes the molecules of the substance to ______more rapidly which we detect by a ______rise in the substance. At point B, the temperature of the substance is ______°C. The solid begins to ______. At point C, the substance is completely ______or in a ______state. Material in this phase has ______volume and ______shape. The energy put to the substance between minutes 5 and 9 was used to convert the substance from a ______to a ______. This heat energy is called the latent heat of fusion.

Between 9 and 13 minutes, the added energy increases the ______of the substance. During the time from point D to point E, the liquid is ______. By point E, the substance is completely in the ______phase. Material in this phase has ______volume and ______shape. The energy put to the substance between minutes 13 and 18 converted the substance from a ______to a ______state. This heat energy is called the latent heat of vaporization. Beyond point E, the substance is still in the ______phase, but the molecules are moving ______as indicated by the increasing temperature.

Which of these three substances was likely used in this phase change experiment?