Key Concepts

For a liquid to dissolve a solid, the molecules of the liquid and solid must tempt one another.The bond between the oxygen and also hydrogen atom (O–H bond) in street (sucrose) provides the oxygen a slight negative charge and the hydrogen a slight hopeful charge. Sucrose is a polar molecule.The polar water molecules entice the negative and positive areas on the polar sucrose molecules which provides sucrose dissolve in water. A nonpolar substance choose mineral oil does not dissolve a polar substance choose sucrose.

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Summary

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

Objective

Students will have the ability to explain, on the molecular level, exactly how the polar characteristics of water and also sugar interact so the water dissolves sugar. College student will have the ability to identify and control the variables in their experiment. College student will also be maybe to describe why a nonpolar liquid, such as mineral oil, is not an excellent at dissolving 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” ingredient of every 5-E great plan.

Safety

Be sure you and the students wear correctly fitting goggles. Isopropil alcohol is flammable. Store it far from flames or spark sources. Read and also follow all warnings top top the label. Dispose of isopropil alcohol and mineral oil follow to regional regulations. Warning studens not to eat the M&M’s.

Materials because that Each Group

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

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

Question come Investigate

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

Materials

Clear plastic cupWaterM&MWhite paper

Procedure

Pour sufficient room-temperature water into clear plastic cup so the the water is deep sufficient to totally cover one M&M and place this cup ~ above a piece of white paper.

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Once the water has actually settled, location 1 M&M in the center of the cup. Be careful to store the water and M&M as still as possible. Observe for about 1 minute.

Expected Results

The coating will certainly dissolve from the M&M, revealing a white great under the color and also then the brown coco underneath. The colored coating that the M&Ms will collect in a circular pattern approximately the M&M. Students may additionally mention the white streaks in the water indigenous the street coating.

Discuss college student observations.

Ask students:

What perform you an alert about the M&M and the water? The shade comes off and also moves v the water in a one pattern. What execute 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 provides the colored coating come off the M&M and also mix into the water, the water is dissolving the sugar and color.

Note: There room actually two procedures happening in this activity. The color and sugar are dissolving in the water yet they are likewise diffusing. In order to emphasis on the amount the dissolves from an M&M, students need to look at the lot of coating lacking from the M&M, rather of the size of the one of color in the water.

Knowing what you do around the polarity of water, why execute you think water dissolves sugar?Students might think that sugar is made of ionic bonds choose salt. Or they can think that sugar has actually positive and an unfavorable areas and also this is why water is attractive to it.Explore

Have students command an experiment come compare exactly 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 friend think water, alcohol, or oil would certainly be much better at dissolve the sugar and color coating of one M&M?

Discuss through students exactly how to style an experiment to compare exactly how well water, alcohol, and also vegetable oil dissolve the color and sugar coating from an M&M. Be certain students identify variables together as:

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

Question to Investigate

Is water, alcohol, or oil much better at dissolve the color and also sugar coating indigenous 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 also Oil. Add 15 mL the water, alcohol, and mineral oil to your labeled cups.Place the three cups ~ above a white sheet of paper.

At the exact same time, include 1 M&M to every liquid. Then 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 just slightly and also the sugar coating doesn’t seem come dissolve.Oil—Neither the shade nor the sugar dissolves