The readings for April 17 included the following line from the book of Revelations 7:9-17, “For the Lamb at the center of the throne will be their Shepherd; ‘He will lead them to springs of living water’”(a reference to Is 40:10). The Old and New Testaments are full of references to water. According to the website Quality-Drinking-Water.com, water is mentioned 722 times in the Bible. If we think about it, it is relatively easy to understand why water would be used, either directly or in metaphor, to express our religion’s message, teachings, and practices. There are not too many other things that are so universally understood by all peoples, all ages, and in all times than the importance of water to our daily existence.
So why is this relatively simple chemical compound so vital to our well-being? It begins with its basic chemical makeup. The chemical formula, H2O, has become part of our common language. The formula shows that two atoms of the element, hydrogen (H), are chemically bound to one atom of the element, oxygen (O) through a sharing of negatively-charged electrons among the atoms.
The molecule looks something like Mickey Mouse’s head, with the two hydrogen atoms being his ears and the oxygen atom being his face. Since oxygen tends to pull the electrons from hydrogen closer to itself, it turns the water molecule into a structure which has a positive pole and a negative pole, similar to a magnet. The polar nature of water gives it many characteristics that make it vital to living things. The positive and negative poles of one water molecule attract the opposite poles of another water molecule. These bonds between water molecules, called hydrogen bonds, give water its cohesive property.
Water molecules bunch together at the water/air surface creating a membrane like phenomenon known as surface tension. This allows insects to scurry along the surface of the water without falling into the water, and also causes water to form raindrops in the atmosphere. Water molecules also adhere to other materials that are also polar in nature. This adhesive property of water can be demonstrated every time a sand castle is built. It is the water sticking to itself and to the sand that holds the sand together. The combination of cohesive and adhesive properties causes what is known as capillary action. This is the ability of water molecules to climb up narrow tubes. Put a small amount of water in a bowl and put a dry sponge in it and you will see capillary action take place as the water rises up into the sponge. Plants, including very large trees, have microscopic tubes that allow water to travel from their roots to the highest part of the plant. Water molecules, which are attached to each other and the surface of the tube, can climb their way up with the help of capillary action.
Water has the ability to dissolve many materials due to its polar nature. It is said to be the universal solvent. This property is critical to our survival. Our bodies are about 60 percent water and it makes up much of our cells. Our blood is 80 percent water. All this water allows us to transport nutrients, like sugars, and gases, such as oxygen, to our cells, and to rid our bodies of waste products, such as salts and urea, and waste gases, such as carbon dioxide. Water also acts to cushion our brains and spinal columns, and to regulate our body temperature through the loss of heat by evaporative cooling during sweating. It also aids directly in digestion in saliva and gastric juices.
Water on our planet is in constant motion. Energy from the sun provides water molecules with the necessary energy to break those hydrogen bonds between them and leave the surface of the ocean, fresh water body, or the soil, and rise as water vapor in the atmosphere by evaporation. Impurities in the water are left behind in the body of water. We no longer see the water because the molecules are too far apart. As the water vapor rises, the molecules spread out and the air mass begins to cool in a process called adiabatic cooling.
Colder air cannot hold as much water vapor as warmer air can. As the air cools it eventually reaches a point that it holds the maximum amount of water vapor that it can and it becomes saturated. The weathermen would say that the relative humidity is at 100 percent. When this happens the air cannot hold any more moisture and condensation occurs on surfaces of dust, salt or other particles in the atmosphere creating clouds. You can observe condensation by taking a cold glass container out of the refrigerator, putting it on the counter, and watching the beads of water form on its outer surface.
In the atmosphere the cohesive property of water brings these small droplets of water together until they become too heavy for the air currents to hold them up, and we get raindrops. This is where our fresh water comes from. Ultimately the water that falls to the earth makes its way back to the ocean by infiltration into the ground to a groundwater aquifer and back to the ocean underground, or, if it falls on a hard surface and cannot penetrate into the ground, it will become surface runoff in streams and rivers and make its way back to the ocean where the cycle continues.
Another interesting property of water is displayed when it freezes. As water cools its molecules get closer together. Below 380 F (40 C) the molecules start to move further apart again as they begin forming the ice crystal. At 320 F (00 C), the volume of the frozen water is nine percent greater than the volume of the liquid water. The ice is less dense than liquid water so it floats. This property of water allows organisms to survive the winter in a pond because the ice forms on the surface and helps insulate the remaining water from the cold.
Pope Francis teaches us in his encyclical, Laudato Si’, that, since water is such a critical part of the existence of all life, it is essential that it be kept clean and available to all. We should not pollute it, or take it away from people for the purposes of selling the water for a profit. We also have a responsibility to conserve it. Jesus taught us to love our neighbors as ourselves. Sharing and caring for the earth’s water resources is another way that we can demonstrate that love.
Anchor columnist Professor Rak is a Fall River native and a parishioner of St. Mary’s Parish in Fall River. He has been a professor of Environmental Technology and coordinator of the Environmental Science and Technology Program at Bristol Community College in Fall River for 18 years. He earned a bachelor’s degree in biology from Holy Cross College in Worcester, and a master’s degree in marine biology from UMass Dartmouth. email@example.com