Try Google's Science Journal App with Six Activities for Chemistry Exploration

By Amy Cowen on September 5, 2018 6:00 AM

With the free Science Journal app, students can start measuring and gathering data right away. We have suggestions for chemistry-focused icebreaker activities to get you and your students started!

Drawn image of an object placed in a cup in front of a smartphone

Try these six chemistry activites with the Science Journal app!

Note: The Google Science Journal app is no longer available. Projects and Lesson Plans at Science Buddies that used the app have been revised to use other sensor apps for mobile devices that have similar functionality. The information below may still be valuable as a starting point for working with sensor-based apps, but please refer to your app for specific information about accessing and using sensor tools.

Google's free Science Journal app (for iOS or Android) gives students a full set of measuring and note taking tools for their STEM projects and everyday explorations. At Science Buddies, we have tutorials developed specifically for students to help them learn to use the app. We encourage teachers to have students bookmark the tutorials page—or use Google Classroom to assign it.

Try the Science Journal App!

If you are curious about Google's Science Journal app but not sure where to get started, we have suggestions! The Science Journal app is designed to be friendly and easy to use. Students can open the app, select a sensor, and immediately start watching data flow across the screen.

Our first 'Try It!' post contained suggestions for using the Science Journal app to measure variables in the classroom (and surrounding) environment. A physics-themed 'Try It!' post is also available. In this post, we have suggestions for six chemistry-focused activities you and your students can try as you get to know the Science Journal app.

Note: Many of the activities you might do using the Science Journal app for chemistry involve liquids. To protect your phone, you may want to seal it in a waterproof plastic bag to help ensure it doesn't get wet.

Note: Several of the activities below involve the light sensor. It is important when doing these exercises that you do not accidentally block the light sensor. You also want to make sure that the materials being used as part of the activity (e.g., a dye tablet, a teabag) do not block the light sensor. If there is ambient light in the room (or ceiling lights that are on), be sure not to cast a shadow on the light sensor, and do not move around during testing as this may change the lighting conditions.

Try these Six Activities

1. Explore the absorption of light by different liquids

Using a few differently-colored drink samples (like fruit juices, sports drinks, and water), students can use the light sensor to explore light absorption and measure how much light can pass through different kinds of beverages. So that you can compare different liquids, pour a small amount (e.g., 1/2 cup) of each liquid into a clear plastic cup. (Be sure to use the same amount for all liquids.) Start a recording and hold one of the test cups containing a liquid over the light sensor on the device. You should see the line on the graph increase and stabilize for that liquid. Hold the cup in place for a second or two and then remove it. After another second or two (a pause in between different liquids), hold another cup with a liquid over the light sensor. Repeat this process with all of the drinks you have available for testing. (Tip: Have students make notes on the order in which the liquids are tested so they can interpret the graph at the end.) What can students determine about the relationship of color of the drink to light absorption based on this activity?

The sample graph below shows several different liquids tested, as described above. The arrows indicate where four different liquids were tested. Looking at this graph, can your students guess which section of the graph reflects the measured light absorption for water, milk, orange juice, and tea?

A screenshot of light absorbed by liquids recorded on a brightness sensor card in the Google Science Journal app. Values on the graph plateau at different levels as different liquids absorb more or less light.

Note: As an alternative to making a single recording of all test liquids, students can take "snapshot" (single readings) for each liquid. By entering a caption identifying the liquid used for each snapshot, they can easily compare the values later.

Important: Keep in mind that Science Journal on iOS and Android use different units to measure "light" (EV on iOS and lux on Android). If you are using multiple devices, note that you will only be able to directly compare data from devices that are using the same unit of measurement. For more information about using the light sensor, see Exploring Light with a Sensor App.

2. Measure Light Absorption Over Time

The longer you leave a tea bag in hot water, the stronger the tea becomes. Does it reach a maximum point of strength? Using the light sensor, students can see the relationship between the "length of time steeping" to the "color" of the tea based on light absorption data. To explore, open the light sensor and start a recording. Carefully pour very hot water into a clear (heat-resistant) cup or glass. Set the cup on top of the light sensor to get an initial reading. Being careful not to block the light sensor, add a single tea bag to the water, and watch the change in the graph. If you continue recording for several minutes, students will be able to observe changes in the color and absorption of the tea as it steeps. Does it reach a point where it no longer changes?

Note: The app will only record when the screen is on. If you are doing a long recording, be sure to tap the screen periodically to keep the phone awake or change your phone's sleep settings.

The screenshot below shows a sample graph from a single cup of black tea steeping, as described.

A screenshot of light shining through black tea recorded on a brightness sensor card in the Google Science Journal app. Values on the graph slowly decrease as the tea steeps and allows less light through.

Tip: You can extend this exploration to test different temperatures of water or different varieties of tea.

3. Listen to a Chemical Reaction

Some chemical reactions make noise. Using the sound sensor in the Science Journal app, students can monitor a chemical reaction by using the app to "listen to" the reaction. To explore, fill a cup or glass 1/3 full (approximately 1/2 cup) with hot or cold water. (Be careful not to fill the cup more than 1/2 full, or the bubbles produced by the chemical reaction may spill over the edges or may splash and hit the phone.) Make sure the testing space is as quiet as possible. Open a sound sensor card in the app and start a recording. Place the device on top of the cup with the sound sensor (microphone) positioned so that it is centered above the cup. (Tip: you may find it helpful to use a second cup of the same size to help balance the device.) What you see on the graph at first represents the ambient noise in the room. Drop an Alka-Seltzer® tablet into the water and watch the graph as the chemical reaction happens and carbon dioxide gas is released. The sound sensor should be able to detect the "fizzing" sound that accompanies the reaction. As the reaction runs its course, students will be able to see from the graph how long the reaction took and how the reaction changed from start to finish. Testing with different temperatures of water lets students explore the relationship between temperature and the rate of the reaction.

The screenshot below shows a sample graph when a chemical reaction between an Alka-Seltzer and a cup of cool water was recorded, as described above.

Screenshot of a recording review for a sound intensity sensor card in the Google Science Journal app

A screenshot of an Alka-Seltzer tablet recorded on a sound intensity sensor card in the Google Science Journal app. Values on the graph increase then slowly decrease as an Alka-Seltzer tablet dissolves in water.

4. Monitor a Dissolution Process

How long does it take for a colored tablet to completely dissolve in a liquid? Using the light sensor app, students can explore this process using water and dye tablets (like the ones that come in an Easter egg coloring kit). Open the light sensor and begin a recording. Carefully set a small clear cup with a small amount (e.g., 1 cup) of hot water on top of the sensor. (You may need to hold onto the cup during this process to keep it balanced.) Drop a single dye tablet into the water. As the dye tablet dissolves, the water will gradually change from clear to colored. Once the tablet has completely dissolved, remove the cup and stop the recording. The graph will allow students to see the dissolution process over time.

The screenshot below shows a sample graph from the activity described using an Easter egg kit color tablet.

A screenshot of light shining through dyed water recorded on a brightness sensor card in the Google Science Journal app. Values on the graph slowly decrease as a dye tablet dissolves and releases pigment into a cup of water.

Note: Dye tablets may dissolve slowly, and the color may not distribute equally without stirring. Students will, however, be able to see the relationship between the light intensity and the darkness of the water.

5. Record Color Removal by Bleach

Using the light sensor, students can monitor reaction kinetics and measure the time it takes for a cup of water to be transformed from colored to clear with the addition of bleach.

Tip: for this activity, you will need bleach that contains 8.35% hypochlorite. Please use caution when using bleach. Wearing rubber gloves and protective eyewear is recommended. Conduct the activity in a well-ventilated room. Be careful not to get bleach on clothing or skin. Wash hands with soap and water thoroughly after the activity.

Prepare a small clear cup with about a cup of room-temperature (or cool) water. Add one drop of food coloring (blue or red) and gently swirl or stir to completely mix the colored water. Open the light sensor. Put the phone in a plastic bag to protect it from spills and lay the phone face up on a flat surface. Position the cup on top of the light sensor. Begin recording. Carefully pour 1/2 tablespoon of bleach (containing 8.35% hypochlorite) into the cup. Continue recording until the sensor reading no longer changes. How long did it take for the bleach to remove the color from the water?

The screenshot below shows a sample graph from the activity described using bleach to remove color from water.

A screenshot of light shining through dyed water recorded on a brightness sensor card in the Google Science Journal app. Values on the graph slowly increase as bleach is added to a cup of dyed water and the water begins to become clear again.

Note: the color of dye used in the activity will affect the time it takes for the reaction. As an extension of the experiment, you may have students test and compare graphs from multiple colors or using different temperatures of water, or have groups of students each test a different color or different temperature of water and compare results as a class.

6. Measure Turbidity of Water

While not all contaminants can be seen with the naked eye, measuring the turbidity of water can offer important information about the quality of drinking water. The turbidity of water is related to how "clear" the water is. Water that is cloudy or has visible particles floating in it may be described as more turbid, for example, than other water. Using the light sensor, students can compare samples of plain water and water with soil or dirt added to it to better understand turbidity.

For the activity, you will want to prepare your water samples first. You will need five clear cups and a small amount (about a 1/2 cup) of very fine dirt. (Fine dirt will stay suspended in the water samples and settle more slowly). Prepare three samples as follows: in one cup, pour 1/2 cup plain (clear) water. In a second cup (medium turbid), add 1/2-1 tsp dirt to 1/2 cup water. In a third cup (very turbid), add 1 1/2-2 tsp dirt to 1/2 cup water. In the cups that contain dirt, stir the dirt into the water. After the big particles settle, pour (decant) the top part of the liquid into a new cup. You will use these new cups for measuring so that no large particles block the sensor.

To test the samples, open a light sensor card in the app. Set the phone face up on a flat surface and start a recording. Place the cup of plain water over the phone's light sensor. Leave it for a few seconds, being careful not to cast shadows over the cup. Remove the cup. Stir the water in the medium turbid sample briefly to stir up any settled particles and place the cup over the phone's light sensor. Leave it for a few seconds, again being careful not to cast shadows. Remove the cup and repeat with the very turbid sample.

The screenshot below shows a sample graph from the activity described. The arrows indicate where three different samples were tested. Can your students guess by looking at this graph which section corresponds to clear, medium turbid, and very turbid water?

A screenshot of light shining through dirty water recorded on a brightness sensor card in the Google Science Journal app. Values on the graph plateau at different levels as different concentrations of dirt are added to cups of water.

Use the Science Journal App with Your Students

The Science Journal app makes it easy to explore the world around you and see science concepts in action. With the app installed on their devices, you can do activities like the ones described above with students.

The video below also highlights seven chemistry-based activities that help show the range of exploration available with Science Journal app.

Fun Chemistry with Google's Science Journal App

https://www.youtube.com/watch?v=Sfu1UUmF2jA

See Try Google's Science Journal App with Five STEM Activities for the Classroom and Try Google's Science Journal App with Five Activities for Physics Exploration for additional quick and easy explorations students can do with the Science Journal app in the classroom or for additional practice using the app.

Science Buddies has independent project ideas for students that work with the app as well as free Lesson Plans for educators that take advantage of the app as part of in-class exploration.

Our tutorial series for Google's Science Journal app is a series of guided walkthroughs developed specifically for students to help them learn to use the app. We encourage educators to have students bookmark the tutorials page—or use Google Classroom to assign it. We recommend that all students using the app read posts 1 and 2. Additional posts are available to help students who will be using specific sensors for their projects.