These are a series of simple demonstrations or hands-on labs to illustrate abstract concepts involved with understanding the chemistry of water and its impact on life. I typically set up the lab at each student's desk (I have lab tables with pairs of students), and then the students complete a single activity before we (as a class) officially define the concept and add it to our notes. By having the students explore each concept prior to any explanation, they gain a deeper understanding. By rearranging the order of the activities, this resource could easily be modified to enhance  any presentation about water chemistry. 

Lab Set Up and Instructions

Set-up: Prior to class, set up student areas with a piece of wax paper, a bowl filled with water, a penny, and an eyedropper. You will also need the following on hand- food coloring, a stalk of celery, two beakers of water, black pepper, a test tube, vegetable oil, two balloons, a flame such as from a bunsen burner or lighter, dish soap, toothpicks, and rubbing alcohol. Note that these demonstrations can be done in any order that makes sense for your presentation. 

Capillary Action: Place a piece of celery in a cup filled with a few inches of colored water at the beginning of class (or at the end of the previous day). Check at the end of class (or the next day) to see how capillary action has moved the water to the top of the stem, well past the surface of the water. The water can be colored with regular food coloring, and the celery can be snapped in half during the final observations to further demonstrate the veins of the plant. 

Surface Tension and Hydrogen Bonds (Cohesion): Gently sprinkle pepper onto the bowl of water at each student's station to demo surface tension. Have students observe how the pepper sits on top of the water. Next have the students dip a toothpick in dish soap and touch the soapy end to the middle of the bowl of water to see the effects of breaking the hydrogen bonds and removing the surface tension. The pepper will be pushed toward the edges and then begin to sink. Without the cohesion between the water molecules on the surface, the pepper is no longer supported. This is now the time to officially discuss surface tension with your students. 

Adhesion and Cohesion: Next have students use the eye dropper to drop water onto a penny and count how many drops will fit. They will then repeat the same steps but this time using rubbing alcohol. They should compare the number of drops between the water and the alcohol. The water will fit more drops because it uses adhesion to stick to the penny and cohesion to stick to one another on top of the penny. Water is a polar molecule, but alcohol is not. Without the polarity, not as much alcohol will stick to the penny. Now is the time to explain polarity, adhesion, and cohesion to the students. 

High Specific Heat: Fill one balloon with water and tie the end. Fill the other with air. Ask the students to predict what will happen to each balloon if held over a flame. Carefully hold the air filled balloon over the flame first. It will pop immediately. Next do the same to the water filled balloon. It will blacken with soot, but it will not pop. Ask the students to try and explain what is protecting the water balloon from the heat of the flame. This is now the time to talk about water's high specific heat, and how it is able to absorb a lot of heat energy without quickly changing temperature. 

Hydrophilic and Hydrophobic Substances: Fill the test tube with equal parts water and oil. Allow the students to make observations. Now shake the tube and allow the liquids to settle back out. Have the students predict why they won't mix. Now have the students put a drop of water containing a single pepper flake onto the wax paper. They should now tilt the wax paper to allow the water drop to "slide" around. However, if they look closely, they can use the pepper to observe that the water actually rolls across the surface of the wax paper. Trying the same demonstration with alcohol will not work as it will simply absorb into the wax paper. In addition, if they drop water onto a sheet of paper, it will absorb. Now is the time to talk about hydrophilic and hydrophobic substances. Be sure to mention that the reason oil and water will not mix is due to the fact that water is polar, but oil is not.