Key Concepts

For a fluid to dissolve a solid, the molecules of the liquid and also solid must attract one another.The bond in between the oxygen and also hydrogen atoms (O–H bond) in sugar (sucrose) offers the oxygen a slight negative charge and also the hydrogen a slight positive charge. Sucrose is a polar molecule.The polar water molecules tempt the an unfavorable and positive locations on the polar sucrose molecules which provides sucrose dissolve in water. A nonpolar substance choose mineral oil does no dissolve a polar substance prefer sucrose.

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Summary

Students will observe the dissolve of the street coating native an M&M as soon as it is placed in water. Students will certainly then assist design one experiment to see if the kind of fluid the M&M is put in affects exactly how much the the coating dissolves.

Objective

Students will have the ability to explain, top top the molecule level, exactly how the polar characteristic of water and also sugar communicate so that water disappear sugar. College student will have the ability to identify and control the variables in your experiment. Students will likewise be able to explain why a nonpolar liquid, such as mineral oil, is not great at dissolve sugar.

Evaluation

Download the student task sheet, and distribute one per student once specified in the activity. The task sheet will certainly serve together the “Evaluate” component of each 5-E class plan.

Safety

Be certain you and also the students wear correctly fitting goggles. Isopropil alcohol is flammable. Save it away from flames or spark sources. Read and also follow every warnings on the label. Dispose of isopropil alcohol and also mineral oil follow to local regulations. Warn studens not to eat the M&M’s.

Materials because that Each Group

M&M’sWaterMineral oilIsopropyl alcohol (70%)Small white plastic plate3 clear plastic cupsWhite paper

Have students location an M&M in a cup that water and observe.

Question to Investigate

What happens to the sugar and also color coating of one M&M when it is put in water?

Materials

Clear plastic cupWaterM&MWhite paper

Procedure

Pour sufficient room-temperature water right into clear plastic cup so that the water is deep enough to completely cover an M&M and also place this cup on a item of white paper.

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Once the water has actually settled, location 1 M&M in the center of the cup. Be mindful to keep the water and M&M together still as possible. Watch for around 1 minute.

Expected Results

The coating will dissolve indigenous the M&M, revealing a white layer under the color and also then the brown chocolate underneath. The colored coating of the M&Ms will certainly collect in a one pattern roughly the M&M. Students may additionally mention the white streaks in the water from the sugar coating.

Discuss college student observations.

Ask students:

What carry out you notification about the M&M and also the water? The shade comes off and moves with the water in a one pattern. What do you think is happening when the color and sugar come off the M&M? allude out to students that due to the fact that the water renders the colored coating come turn off the M&M and also mix right into the water, the water is dissolve the sugar and also color.

Note: There are actually two processes happening in this activity. The color and also sugar room dissolving in the water but they are additionally diffusing. In bespeak to emphasis on the amount the dissolves from an M&M, students must look at the quantity of coating lacking from the M&M, rather of the dimension of the one of shade in the water.

Knowing what you do around the polarity the water, why carry out you think water dissolves sugar?Students might think the sugar is do of ionic bonds prefer salt. Or they could think that sugar has actually positive and an adverse areas and this is why water is attractive to it.Explore

Have students command an experiment to compare just how well water, alcohol, and also oil dissolve the sugar and color coating of one M&M.

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Ask students to do a prediction:

Do you think water, alcohol, or oil would certainly be far better at dissolving the sugar and color coating of one M&M?

Discuss through students just how to style an experiment come compare how well water, alcohol, and also vegetable oil dissolve the color and also sugar coating native an M&M. Be sure students identify variables such as:

Amount of water, alcohol, and also oil usedTemperature of every liquidSame shade of M&MTime and also location the M&M’s are placed in each fluid

Question come Investigate

Is water, alcohol, or oil much better at dissolve the color and sugar coating from an M&M?

Materials

3 M&Ms (same color)WaterMineral oilIsopropyl alcohol (70%)3 clear plastic cupsWhite paper

Procedure

Label 3 cup Water, Alcohol, and Oil. Add 15 mL of water, alcohol, and also mineral oil to your labeled cups.Place the 3 cups ~ above a white paper of paper.

At the very same time, add 1 M&M to each liquid. Climate gently swirl the liquid and also M&M in every cup for about 30 seconds.

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Expected Results

Water—The sugar and color dissolve native the M&M. Alcohol—The shade dissolves only slightly and the sugar coating doesn’t seem to dissolve.Oil—Neither the color nor the sugar dissolves