Questions:
1. In this activity, what are you investigating?
2. State your hypothesis.
3. Design a controlled experiment to test your hypothesis.
4. What variables are you controlling in your experiment?
5. What data will you collect? How will you collect and organize this data?
6. What conclusions can you draw from the results of your experiment?
Answers:
1. Investigating the effect of salt on the melting temperature of ice.
2. Hypothesis: If salt is added to ice, then the ice will melt at a lower temperature.
3. Controlled experiment:
- Materials: ice, salt, water, 2 containers
- Procedure:
- Place equal amounts of ice in each container.
- Add salt to one container and water to the other.
- Stir the contents of each container until all the ice has melted.
- Record the temperature of the water in each container.
4. Controlled variables: type of ice, amount of ice, amount of salt/water, temperature of the room
5. - Data: temperature of the water in each container
- Collect and organize data in a table:
| Container | Temperature (°C) |
| ------- | -------- |
| Ice + Salt | 0 °C |
| Ice + Water | 0 °C |
6. Conclusions:
- The ice in the container with salt melted at a lower temperature than the ice in the container with water.
- This supports the hypothesis that salt lowers the melting temperature of ice.