Without water, life would not be possible. For that reason, astronomers are constantly looking for other locations in the universe where liquid water might exist. Only in such places could there be any hope of finding life. Whether life exists anywhere in the universe outside of planet Earth is a question people have asked for hundreds of years. Scientists still don’t know the answer, but everyone agrees that there could be no life without water.
The water molecule seems very simple. It is H2O–one oxygen atom combined with two hydrogen atoms. However, instead of bonding in a straight line (H-O-H), the two hydrogen atoms are on one side of the water molecule at a 104.5-degree angle from each other. That alignment gives the hydrogen side of the water molecule a partial positive charge, while the other side has a partial negative charge. Because of that, the positive and negative sides of water molecules attract one another and form hydrogen bonds resulting in a network of water molecules.
When water is in the gaseous state, the interaction between molecules is negligible. However, when it is in the solid form of ice, each water molecule forms a bond with four others, creating a lattice that causes ice to be lighter than liquid water. For most substances, the solid state is heavier than the liquid state. This unique property of water causes ice to float. Additionally, the low thermal conductivity of ice prevents the water below from freezing. If lakes and oceans froze from the bottom up, it would kill all marine life and ultimately all life on Earth.
If water molecules did not form hydrogen bonds, instead of boiling at 100 degrees C, water would boil at -100 degrees C. That would prevent life processes. Furthermore, because there is a 100 degree C difference between water’s melting and boiling points, life is possible in Earth’s wide range of environments. Water has the highest heat of evaporation of any known substance so that it remains liquid up to and even at its boiling point. It also has the second-highest heat capacity of any known substance, allowing its temperature to remain stable during heat fluctuations in the environment. Those qualities of water are also critical for life, meaning that there could be no life without water.
Water’s ability as a solvent makes it essential for the life processes of living cells. Likewise, water’s inability to dissolve oily substances is vital to create a strong “hydophobic effect.” Cell membranes, DNA, RNA, and proteins all contain oil-like regions. If the water in the cells could dissolve them, life would not be possible. In addition, the water molecule can participate in and enable chemical processes such as hydrolysis, reduction, oxidation, and others that are essential in living cells.
The bottom line is that there is no life without water and the fine-tuning of the hydrogen bonding in water molecules. With new scientific discoveries, we see fine-tuning for life in the cosmos and even in the cells of our bodies. Without that fine-tuning, life would not exist, and we would not be here. Accidental coincidences do not explain such incredible precision of design. We think the explanation goes beyond science and points to an intelligent Designer.
— Roland Earnst © 2022
For much more on this, read chapter three, “The Chemical Anthropic Principle,” in Fazale Rana’s book Fit for a Purpose.