Video Supplements: Time
Plop, Plop, Fizz, Fizz — Timing Race

Overview
Using the analogy of an upset stomach in quick need of an antacid, this lesson helps students practice calculating time and reading thermometers.

Outcome
Students will measure temperature and practice measurement conversions.

Standards Addressed — Mathematics

Grade 3
Measurement Units, Benchmark A
01. Identify and select appropriate units for measuring temperature in degrees (Fahrenheit or Celsius).

04. Read thermometers in both Fahrenheit and Celsius scales.

Grade 5
Use Measurement Techniques and Tools, Benchmark B
05. Make conversions within the same measurement system while performing computations.

 

Standards Addressed — Data Analysis and Probability

Grade 4
Data Collection, Benchmark B
02. Represent and interpret data using tables, bar graphs, line plots and line graphs.

Data Collection, Benchmark C
02. Represent and interpret data using tables, bar graphs, line plots and line graphs.

Grade 5
Data Collection, Benchmark E
02. Select and use a graph that is appropriate for the type of data to be displayed; e.g., numerical vs. categorical data, discrete vs. continuous data.

Materials

• Effervescent antacid tablets (such as Alka Seltzer)

• Two water containers per group

• Stop watch or clock with a second hand

• Thermometer

• Eye protection

• Warm and cold water

• Plop, Plop, Fizz, Fizz student handout

Procedure

1. Divide the class into groups of two or three.

2. Ask students if they have ever taken an antacid tablet or know anyone who did. Describe how an antacid is used to give relief from an upset stomach.

3. Discuss the idea of getting relief from your discomfort as quickly as possible. Tell students that we’re going to try an experiment to see if we can get quicker comfort.

4. Give each student two antacid tablets and a water container.

5. Ask the students to get water ranging from hot water (but not so hot that the students would get burned) to cold water. Have ice available and perhaps a warming plate. Try to get a wide variety of temperatures. They can take hot water and add a little ice to get a different temperature.

6. Have the students measure the temperature of the water using either the Celsius or Fahrenheit scale, depending upon your preference.

7. Once they have an accurate reading, they should drop the antacid tablet in the water and measure how long it takes to completely dissolve. They should mark the time in seconds.

8. As a separate activity, students can convert the time to minutes.

9. They should record the ordered pair (temperature, time) on the board or overhead.

10. When all temperatures have been recorded, students should make a graph with temperature on the x-axis (the independent variable) and time on the y-axis (the dependent variable). This indicates that the time it takes for the tablet to dissolve is dependent upon the temperature of the water.

11. Students should write a summary telling what the graph is telling them.

12. Extension #1: Students can experiment to see if the surface area of an antacid tablet plays a role in how quickly it dissolves. “Students will learn that increasing the surface area of a tablet by crushing it into a powder increases its reaction rate with the water. This is a similar situation to the way a rocket’s thrust becomes greater by increasing the burning surface of its propellants.” (Source: NASA, Rockets: An Educator’s Guide with Activities in Science, Mathematics and Technology, EG-2003-01-108-HQ)

13. Extension #2: There is a great science correlation in this activity. The experiment measures the reaction rate of tablets in different water temperatures. “Tablets in warm water react much more quickly than tablets in cold water. In liquid propellant rockets engines, super cold fuel, such as liquid hydrogen, is preheated before being combined with liquid oxygen. This increases the reaction rate and thereby increases the rocket’s thrust.” (Source: NASA, Rockets: An Educator’s Guide with Activities in Science, Mathematics and Technology, EG-2003-01-108-HQ)

Evaluation

Rubric for Graph