Investigation Sequence


Mixture Sequence

Written by:

Diatra Woodward and Tara Kramer                 Date


Focus Questions

What is a mixture? How do you know and why?


Content: Earth, Physical, & Life

A mixture is a combination of substances.

Cross cutting concepts


Science Practice


Personal, Social, Technology, Nature of Science, History


Background information

A mixture of substances can be separated back to the original substances by using one or more of the characteristic properties (filtration, evaporation, etc.). Compounds are different than mixtures in that they combine to form new substances. (For example salt and sugar together is a mixture because salt and sugar do not bond together. Salt itself is a compound with sodium and chloride atoms bonded together. Salt is quite different from either of these two substances.) Solutions are a mixture where a solid dissolves in a liquid. The substance that dissolves is called a solute. The liquid in which it dissolves is called a solvent.additionalinfo

Activity Sequence

1. Paper clip and nickels
2. Salt and sugar mixture
3. Make a mixture/separate a mixture
4. Sugar and water
5. Sand and salt water
6. Dissolving solids in warm and cold water

Activity Descriptions

Activity 1
Paper clips and nickels
Several nickels and paper clips, magnet, science journal/drawing materials
1. Ask students if they have ever tried to separate objects in a mixture (i.e. raisins from corn flakes, marshmallows from cereal, etc.)
2. Listen to responses. Do not comment on accuracy.
3. Ask the students what they would do in order to sort a mixture of nickels and paper clips into groups without touching them.
4. Ask students how they could record their data.
5. Have students try to separate the nickels from the paper clips without touching them and have them record the data.
6. Have them share their data/drawings.
7. Ask students to interpret results.
8. Ask where they could use the same idea.

Activity 2
Salt and sugar mixture
Salt crystals, sugar crystals, plastic sup, magnifying glasses, science journal/drawing materials
1. Ask students what will happen when they mix salt and sugar together
2. Listen to responses. Do not comment on accuracy.
3. Ask students how to tell the two substances apart.
4. Have students observe the mixture and record data.
5. Have them taste it to see that it retains both the sweet and salty tastes.
6. Have students share their data/drawings.
7. Ask students to interpret results.
8. Ask students where they could see the same results at home.

Activity 3
Make a mixture or separate a mixture
Variety of fruits and vegetables, bowl of party mix, variety of drink mixes, brownie ingredients
1. Ask students what a mixture is.
2. Ask students how they could separate the items of a mixture.
3. Separate students into groups.
4. Give the following directions: Group A – make a mixture using a variety of fruits. Group B – separate the items in a bowl of party mix. Group C – Make mixtures using various types of drink mixes. Group D – make a mixture using brownie ingredients.
5. Have students discuss the results.
6. Ask students how they could use what they learned.

Activity 4
Sugar and water
Teaspoon, clear bowls/glasses, sugar, and water
1. Ask students to predict what will happen when sugar is added to water.
2. Give students the clear glasses, bowls, sugar, and water.
3. Allow the students to put sugar in the water.
4. Have the students record what they observe while doing the experiment.
5. Ask the students to describe what happened.
6. Ask students to problem solve how to separate the mixture of sugar and water.
7. Try their suggestions.
8. Ask the students when they have or could use this information at home.

Activity 5
Sand and salt water
Sand, tablespoon of salt, drinking glass, water, coffee filter, plate, science journal
1. Give students a drinking glass, water, sand, and salt and ask them to use these to make a mixture.
2. Once the students have created a mixture, ask them to problem solve how they could separate each part of the mixture.
3. List their ideas on the board.
4. Let the students experiment using different ideas listed on the board.
5. Have students draw (before, during, and after) pictures in their journals.
6. After they have separated the sand, have them share the methods they used and whether these methods were very efficient.
7. Have them predict what will be left after the water evaporates.
8. Have students compare predictions in actual results.
9. Ask students to think of why separating a mixture is useful.

Activity 6
Dissolving solids in warm and cold water
Clear glasses (14 for each group), warm and cold water, small amounts of soil, flour, cocoa, tea, coffee, pepper, baking soda, and baking powder, stir sticks, science journal
1. Ask what happened when water is added to sugar.
2. Have the students list some other solids similar to sugar.
3. Ask if they think the same thing would happen with these other solids.
4. Ask students if they think the temperature of the water would make a difference. Write predictions on the board.
5. Have the students predict what will happen to each substance before pouring in warm or cold water in and write predictions down.
6. Have the students put a small amount of soil in two clear cups. Add warm water in one and cold water in the other. Repeat this process with each substance.
7. Have students record their results on the attached chart.
8. After they have added the water to all the items, have them stir each one to see if that helps mix it together. Record these results on the chart.
9. Have students let all the mixtures sit for five minutes. Record what (if anything) happens after it has been sitting.
10. Ask students to compare their findings.
11. Have them brainstorm as to why some things react differently with warm water instead of cold water. Ask if these things are all mixtures.

Dr. Robert Sweetland's notes