Mystery Milk ProjectMystery Milk Project

Purpose: How does it work?Purpose: How does it work? HypothesizeHypothesize how and why you how and why you

think that this occurs.think that this occurs.

What makes the What makes the

swirling of the food swirling of the food

coloring occur? coloring occur? TalkTalk about it with about it with

your partners.your partners.

Then Then writewrite your ideas in your your ideas in your science journals. science journals.

Materials:Materials:

- Milk - Milk -Petri Dish-Petri Dish

- Food coloring (red, yellow, - Food coloring (red, yellow, green, blue)green, blue)- Dish-washing soap - Dish-washing soap

- Cotton swabs- Cotton swabs

Procedures:Procedures: 11. . PourPour enough enough milkmilk in the pie tin to completely cover the in the pie tin to completely cover the

bottom and allow it to settle. bottom and allow it to settle.

22. Add one . Add one dropdrop of each of the four colors of of each of the four colors of food food coloringcoloring - red, yellow, blue, and green - to the milk. Keep - red, yellow, blue, and green - to the milk. Keep the drops close together in the center of the plate of milk in a 3, the drops close together in the center of the plate of milk in a 3, 6, 9, 12 o’clock formation.6, 9, 12 o’clock formation.

33. Find a clean cotton swab for the next part of the experiment. . Find a clean cotton swab for the next part of the experiment.

PredictPredict what will happen when you touch the tip of the what will happen when you touch the tip of the cotton swab to the center of the milk. It's important not to stir the cotton swab to the center of the milk. It's important not to stir the mix just touch it with the tip of the cotton swab. mix just touch it with the tip of the cotton swab.

44. Place a . Place a dropdrop of liquid of liquid dish soapdish soap (the Dawn brand (the Dawn brand works well) on the tip of the cotton swab. Place the soapy end works well) on the tip of the cotton swab. Place the soapy end of the cotton swab back in the middle of the milk and hold it of the cotton swab back in the middle of the milk and hold it there for 10 to 15 seconds. there for 10 to 15 seconds.

Observed:Observed:Look at thatLook at thatburst of color! burst of color! It's like the It's like the 4th of July in a 4th of July in a bowl of milk: bowl of milk: mini-explosionsmini-explosions of color. of color.

Step 5. Add another drop of soap to the tip to Step 5. Add another drop of soap to the tip to the cotton swab and try it again. the cotton swab and try it again.

Experiment with placing the cotton swab at Experiment with placing the cotton swab at different places in the milk. different places in the milk.

Notice that the colors in the milk continue to Notice that the colors in the milk continue to move even when the cotton swab is move even when the cotton swab is removed. removed.

What makes the food coloring in the milk What makes the food coloring in the milk move? move?

What make the swirling of the What make the swirling of the food coloring occur? food coloring occur? Liquid soap wrecks the surface tension by Liquid soap wrecks the surface tension by

breaking the cohesive bonds between breaking the cohesive bonds between water molecules and allowing the colors to water molecules and allowing the colors to zing throughout the milk. zing throughout the milk.

In this experiment the liquid soap weakens In this experiment the liquid soap weakens the milk’s bonds by attaching to its fat the milk’s bonds by attaching to its fat globules because of its bipolar globules because of its bipolar characteristics (hydrophilic on one end and characteristics (hydrophilic on one end and hydrophobic on the other). hydrophobic on the other).

The soap's hydrophilic end dissolves in The soap's hydrophilic end dissolves in water and its water-fearing end attaches to water and its water-fearing end attaches to a fat globule in the milk. a fat globule in the milk.

What is it about milk that makes it What is it about milk that makes it have surface tension? have surface tension?

Since milk is mostly water, it has Since milk is mostly water, it has surface tension like water. The surface tension like water. The drops of food coloring floating drops of food coloring floating on the surface tend to stay put. on the surface tend to stay put. Water has surface tension Water has surface tension because of the attraction of all of because of the attraction of all of the molecules. In the bulk of the the molecules. In the bulk of the liquid each molecule is pulled liquid each molecule is pulled equally in all directions by equally in all directions by neighboring liquid molecules.neighboring liquid molecules.

Atom: the smallest basic unit of Atom: the smallest basic unit of matter.matter.

Compound: atoms of different Compound: atoms of different elements bonded together in a elements bonded together in a certain ratio.certain ratio.

Molecules: two or more atoms held Molecules: two or more atoms held together by a chemical bond.together by a chemical bond.

Element: one type of atom (each Element: one type of atom (each have different number of protons) have different number of protons)

Unique Properties of water Unique Properties of water

This experiment can This experiment can explain surface tension explain surface tension and polarity. The and polarity. The explanation of surface explanation of surface tension can show all of tension can show all of the things that make the things that make water so useful for life. water so useful for life. For example, waters For example, waters surface tension comes surface tension comes from its polarity such that from its polarity such that it is attracted to itself. it is attracted to itself. This makes certain things This makes certain things like the capillary effect like the capillary effect possible so that plants possible so that plants may “drink” water from may “drink” water from the ground. This also the ground. This also explains the structure of explains the structure of ice and why the solid ice and why the solid form of H2O is less form of H2O is less dense than the liquid dense than the liquid stage.stage.

Phospholipid BilayerPhospholipid Bilayer This characteristic behavior of This characteristic behavior of

water and oil is of critical water and oil is of critical importance for living things, importance for living things, determining many properties determining many properties of the cell of the cell

Phospholipids, the building Phospholipids, the building blocks of the cell membranes, blocks of the cell membranes, are both are both hydrophilic and hydrophobichydrophilic and hydrophobic. .

The hydrophobic pair of fatty The hydrophobic pair of fatty acids are embedded in the acids are embedded in the middle of the membrane.middle of the membrane.

The hydrophilic phosphate The hydrophilic phosphate projects outward forming projects outward forming hydrogen bonds hydrogen bonds with a tight, with a tight, organized layer of water on organized layer of water on each face of the membrane.each face of the membrane.

What is it about soap that What is it about soap that allows for oils to be dissolved? allows for oils to be dissolved? Soap has a part of the molecule that Soap has a part of the molecule that

is polar and nonpolar. When washing is polar and nonpolar. When washing with water alone, it will not dissolve with water alone, it will not dissolve oils, but when soap is added to the oils, but when soap is added to the water, the polar end of the soap water, the polar end of the soap molecules is attracted to the polar molecules is attracted to the polar end of the water molecules and the end of the water molecules and the nonpolar end is absorbed into the oil. nonpolar end is absorbed into the oil. A particle (larger than a molecule) is A particle (larger than a molecule) is formed and the oil can be washed formed and the oil can be washed away with water.away with water.

HomogenizationHomogenization This experiment explains what homogenization of milk This experiment explains what homogenization of milk

is. Milk is made up mostly of water and then equal parts is. Milk is made up mostly of water and then equal parts of protein, fats, and sugar. The fat has been broken up of protein, fats, and sugar. The fat has been broken up and spread throughout the milk (by the process called and spread throughout the milk (by the process called HOMOGENIZATION) into tiny pieces of fat called HOMOGENIZATION) into tiny pieces of fat called globules. globules.

When the milk was first placed into the carton, it was still When the milk was first placed into the carton, it was still and did not move. Even when the food coloring was and did not move. Even when the food coloring was added to the milk, things were still quiet. This is because added to the milk, things were still quiet. This is because the fat globules were steady and undisturbed. the fat globules were steady and undisturbed.

When the soap hits the milk, things begin to move. The When the soap hits the milk, things begin to move. The soap breaks up the fat globules and lets them spread soap breaks up the fat globules and lets them spread across the surface of the milk. When you add soap, the across the surface of the milk. When you add soap, the weak chemical bonds that hold the proteins in solution weak chemical bonds that hold the proteins in solution are altered. are altered.

As the globules break and expand, they create As the globules break and expand, they create movement in the milk. Normally you would never notice movement in the milk. Normally you would never notice this, but the food coloring shows how the surface of the this, but the food coloring shows how the surface of the milk moves and changes in response to the soap milk moves and changes in response to the soap breaking up the fat in the milk.breaking up the fat in the milk.

How soap worksHow soap works

This experiment explains how soap works. Soap This experiment explains how soap works. Soap has a part of the molecule that is polar and has a part of the molecule that is polar and nonpolar. nonpolar.

When washing with water alone, it will not dissolve When washing with water alone, it will not dissolve oils, but when soap is added to the water, the polar oils, but when soap is added to the water, the polar end of the soap molecules is attracted to the polar end of the soap molecules is attracted to the polar end of the water molecules and the nonpolar end is end of the water molecules and the nonpolar end is absorbed into the oil. A particle (larger than a absorbed into the oil. A particle (larger than a molecule) is formed and the oil can be washed molecule) is formed and the oil can be washed away with water. away with water.

In this experiment the liquid soap weakens the In this experiment the liquid soap weakens the milk’s bonds by attaching to its fat globules because milk’s bonds by attaching to its fat globules because of its bipolar characteristics (hydrophilic on one end of its bipolar characteristics (hydrophilic on one end and hydrophobic on the other). The soap's and hydrophobic on the other). The soap's hydrophilic end dissolves in water and its water-hydrophilic end dissolves in water and its water-fearing end attaches to a fat globule in the milk. fearing end attaches to a fat globule in the milk.

Soap