How the Mpemba Effect Works

How the Mpemba Effect Works
One oxygen atom and two hydrogen atoms bond to form a water molecule

Yesterday, I warned of the danger of trying to solve an argument using the scientific method when people want to stick to their preconceived ideas. The argument I referred to was between my family members about whether hot or cold water freezes faster. The truth is that the phenomenon where hot water freezes faster is called the Mpemba effect after an African secondary school student who brought it to the attention of a British physicist. Even though it had been observed since Aristotle’s time, most people didn’t believe it, and nobody seriously attempted to explain how the Mpemba effect works.

Perhaps the reason science ignored the Mpemba effect is because it seems illogical and unreasonable. In 2013, Xi Zhang and colleagues at Nanyang Technical University in Singapore presented a possible solution to how the Mpemba effect works. Water molecules contain one atom of oxygen bonded to two atoms of hydrogen (H2O). The oxygen atom shares an electron with each hydrogen atom in what is known as covalent bonding.

In addition to the covalent bonding within the water molecules, the separate molecules are held together by hydrogen bonds. Water molecules are polarized, and since water is a liquid, the molecules move around. When a hydrogen atom in one molecule is close to the oxygen atom in another molecule, hydrogen bonds loosely hold them together. Hydrogen bonds explain the surface tension of water, its relatively high boiling point, and how the Mpemba effect works.

As water is heated, the molecules move faster, stretching the hydrogen bonds, causing them to store energy, and allowing the covalent bonds to relax and give up some energy. Covalent bonds giving up energy is equivalent to cooling, allowing the heated water to freeze faster. In a 2017 issue of the Journal of Chemical Theory and Computation, Yunwen Tao and co-authors described using vibrational spectroscopy and modeling to show that hydrogen bonds can explain how the Mpemba effect works.

Other factors can be involved in water freezing to counter the Mpemba effect. Dissolved gases or other impurities, convection currents, evaporation, and even the container can influence the time it takes for water to freeze. The relative initial temperatures and consistency of the water samples are also critical factors.

The bottom line is that the design of water is an essential factor that makes life possible. We have said that before: HERE, HERE, HERE, HERE, and HERE. The fact that hot water can freeze faster than cold is hard to believe, but true. Even harder to believe is that the design of water, the universe, our planet, and life could be accidental, but atheists still argue that those designs all happened by chance. I challenge you to carefully consider where you stand on the existence of a creator God.

— Roland Earnst © 2023

References: Gizmodo.com and wikipedia.org

Relativity, Quantum Mechanics, and Complex Electron Orbitals

Relativity, Quantum Mechanics, and Complex Electron Orbitals

Yesterday, we said that the simple atomic model shown in older chemistry textbooks leaves many mysteries unanswered. During my 50 years of teaching chemistry, students sometimes asked questions that could not be explained by electrons in circular orbits. In recent years, spectral analysis has shown that electrons travel in various orbital patterns that may be dumbbell or clover-leaf shaped. In addition, quantum mechanics has shown that electrons can act like waves rather than particles. Relativity, quantum mechanics, and complex electron orbitals explain some of the mysteries of chemistry.

For example, oxygen has a first shell with two s-type electrons traveling in circular orbits and four more in dumbbell-shaped p orbits. That second shell can hold six electrons, leaving openings for two more orbitals 90 degrees apart. If a hydrogen atom with one electron comes nearby, it will bond with the oxygen, each of them sharing an electron. If two hydrogens bond with the oxygen atom, you have a perfect, stable combination – a water molecule

In the water molecule, the hydrogen atoms repel each other, creating a 180-degree angle between them and giving the water an electrical polarity. The result is that water molecules have a positive and negative end, and as they freeze, they repel each other, expanding their volume. Because of that, ice is less dense and floats on top of the water instead of sinking to the bottom. If bodies of water froze from the bottom up, life on Earth would be impossible.

What makes this picture even more interesting is that electrons can orbit at a speed that is 60% of the speed of light or faster. At that speed, their mass increases, and their orbit contracts in conformity with Einstein’s relativity equations. Relativity, quantum mechanics, and complex electron orbitals combine to explain the mysteries of chemistry. For example, the relativity contraction makes it harder for mercury atoms to interact strongly with each other. As a result, mercury is a liquid, while other metals are solids at room temperature. 

Relativity and quantum mechanics also explain the difference in color between gold and silver. Relativistic effects in the electron orbitals cause silver to reflect all wavelengths of visible light equally. Because of that, it has no particular color. On the other hand, gold’s electron orbitals cause it to absorb blue light, making the reflected light appear yellow. 

Relativity, quantum mechanics, and complex electron orbitals are opening new understandings in chemistry, allowing new techniques to aid in improving life for all humans. For example, doctors use radioactive technetium and rhenium as tracer molecules in medical imaging because of the effects of relativity. Understanding relativity and electron orbitals explains the formation of lead dioxide, which is essential for lead-acid auto batteries. Relativity in electron orbitals even plays a role in “glow-in-the-dark” items such as signs, stickers, and T-shirts.

The complexity of atoms is a testimony to the intelligence and engineering of the Creator. We are continually reminded that we can know there is a God through the things He has made. The challenges and the future of relativistic chemistry are a great testimony to that. 

— John N. Clayton © 2023

Reference: “Relativity and the World of Molecules” by Abhik Ghosh and Kenneth Ruud in American Scientist magazine for May/June 2023 

Electron Orbitals of Oxygen and Nitrogen

Ice Covered Lake and Electron Orbitals of Oxygen and Nitrogen
Ice floats because it is lighter than water, and that is because of electron orbits.

Last week (January 13-15), we talked about the electron structures of oxygen and nitrogen and the importance of those elements for life. One additional design feature is the electron orbitals of oxygen and nitrogen, which is the shape of the electron paths around the nucleus.

Electrons do not revolve around the nucleus in simple circles but rather in geometric paths. For example, the oxygen atom has two electrons that orbit the nucleus in a circular pattern. A little further out and at a higher energy level, two more electrons move in a circular path. Oxygen has eight electrons, and the four electrons in the last energy shell, the valence shell, have a different orbital.

In the third energy level, the orbitals of the four electrons have figure-eight paths at right angles to each other. This figure-eight pattern has two electrons isolated from the other two and each at right angles to the other. That arrangement enables the oxygen atom to form an essential polar molecule.

When an oxygen atom combines with two hydrogen atoms by covalent bonding, they form a molecule of water, H2O. The water molecule has the two hydrogen atoms positioned at one end, making it positive, while the other end of the water molecule is negative. This polar structure gives water its unique properties. For example, water expands as it freezes, causing ice to be lighter than the liquid form. Because of that, ice floats on the surface of a lake instead of sinking to the bottom and freezing the entire lake, killing all marine life. The polar nature of water also allows it to dissolve minerals.

With its seven electrons, nitrogen has five valence electrons moving at right angles to each other, allowing it to form critical organic compounds. For example, nitrogen bonds covalently with three hydrogen atoms to form ammonia which has properties very different from water. Nitrogen’s ability to form three bonds makes possible the structure of the DNA in our cells.

This very simplified description of the atomic design of chemistry gives a small glimpse of the wisdom of design God put into the electron orbitals of oxygen and nitrogen. The Master Chemist designed the structures of atoms to allow life to exist in an incredible number of forms and thrive in a wide range of environments.

— John N. Clayton © 2022

Life Requires Polar Molecules

Life Requires Polar Molecules - Watere

Chemistry is a fascinating science. The design of atoms and molecules allows life to exist. Science fiction writers have tried to convince us that there could be life out in space that is radically different from life on Earth. The subject of this discussion is not whether there is life on other planets or moons. If God created it, then it will be there, and we will find it. But life requires polar molecules.

Skeptics have maintained that to be open-minded about life in space, we must look for life based on something other than the CHNOPS. (CHNOPS is carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur.) Why not life based on silicon, iridium, cesium, iron, and chlorine?

A basic biology principle that most of us learned in high school is that to exist, life requires polar molecules. That means there has to be an abundance of a molecule with a positive and a negative end. On our planet, the molecule that meets that requirement is water.

The oxygen molecule is designed so that when it combines with two hydrogen atoms, it forms a water molecule that has a positive and a negative end. This design enables water to do a variety of things necessary for life. Water moves things around, dissolves other compounds, conveys nutrients into cells, and carries away waste. Other polar molecules, like amino acids, proteins, or DNA, could not be manipulated and used without water. Life requires polar molecules.

Astronomers have discovered methane and ethane on planets and moons throughout space, but they cannot support life because they are not polar. The media have brought attention to the moons Titan and Europa, which both seem to have oceans and rivers of methane and ethane. Other moons such as Enceladus, Ceres, Ganymede, Callisto, Dione, and Triton are chemically active and have some water, but they are dominated by non-polar chemicals. Chemical studies of the 4000 plus exoplanets astronomers have discovered do not show any other polar molecules in abundance.

Life has to follow some basic rules. One of those rules requires polar molecules in abundance for any kind of life to exist. An oxygen atom has eight electrons, but its structure allows only four electrons in its outer orbit. That is important because the outermost orbit is the only one that allows other elements to share electrons to make a compound. The four inner-orbit electrons with their negative charge cannot be shared. That automatically means that the oxygen side of any compound, such as water, will be negative, and the other side will be positive. This principle is the starting point for biochemistry, and it is a design invented by an Intelligence that established the rules for life.

When my students saw this in basic chemistry, there was always someone who would say, “Wow! Who thought that up?” As a public high school teacher, I was not allowed to say “God,” but the message is clear without being said.

— John N. Clayton © 2020

For more on this, see the article titled “Looking for Life in the Universe” by Dr. Morgan Cable in the January 2021 issue of Astronomy magazine (page 46-48). Dr. Cable is the supervisor of the Astrobiology and Ocean Worlds Group at the NASA Jet Propulsion Laboratory. Her research is about looking for life and habitability in space

Moving Heat Energy

Moving Heat Energy
Winter always reminds us of how important it is to have ways of moving heat energy from one place to another. We are considering how the complex heat transfer system is another evidence for God’s creative wisdom. Yesterday we looked at heat transfer by radiation. There are two more methods.

A second way of moving heat energy is by conduction. When you put a spoon into a hot cup of water the molecules that make up the spoon begin to vibrate faster as they absorb heat energy from the water. As one molecule gets energy, it bumps into the next molecule, and it also starts to vibrate. This happens down the length of the spoon, and eventually, the heat is conducted to your skin.

How fast heat conduction happens depends upon the size, mass, and density of the material in the object conducting the heat. Gases have poor conductivity because their molecules are far apart. A winter coat has lots of spaces between the fabric molecules filled with air. Fur has air spaces between the hairs and inside the hair strands themselves. Those low-density spaces insulate against heat transfer. You have heard the old story about never putting your tongue on a very cold metal object. The reason is that the water in your tongue conducts heat away to the metal surface which is very dense. The heat transfer process happens so fast that the water in your tongue freezes.

A third method of moving heat energy is by convection. Heating air or water is difficult by radiation alone or by conduction alone. The materials are transparent, so they absorb radiation poorly. Conductivity is slow and limited as to how far the heat can travel. What happens is that molecules change their density as they are heated or cooled. When heated, the gas or liquid becomes less dense it rises taking heat energy with it. As it cools, it sinks because it becomes denser. The motion mixes the hot and cold in the process we call convection.

The amazing ability of water to change its density as it is heated and cooled allows lakes to form ice on the surface rather than on the bottom. Water was designed to have its lowest density at 32 degrees Fahrenheit. It has a higher density both above and below that temperature. A very complex chemical property of water is designed to handle the heat energy by becoming more dense down to 32 degrees and then less dense as it freezes into ice. You can read more about this essential characteristic of water in THIS PREVIOUS POST and in our book Dandy Designs Volume 3, available HERE.

We take for granted the various methods of moving heat energy in and around us, but the complexities of this design are amazing. My physics students love to see how this allows us to exist on this planet.
–John N. Clayton © 2019

Oxygen Atom Design and Water

Oxygen Atom Design and Water
In our post for yesterday (July 7, 2018) we dealt with oxygen as a designed feature promoting life by allowing us to breathe. Another interesting design feature relates to the oxygen atom design and water. The oxygen molecule’s design allows water to have the properties that it has.

The oxygen atom has eight electrons in orbitals based on their energy with the electrons paired so that their magnetic polarities are balanced. Each electron is essentially a little magnet with a north and a south pole. When the electrons are together in a pair, one electron’s north pole matches up with the second electron’s south pole. In oxygen, the first two electrons are in what is called the S orbital. The next energy level out is also an S orbital with two electrons. The third energy level out from the nucleus is the P orbital. This orbital can hold six electrons, but oxygen has only four electrons left. Two of the electrons are paired, but the remaining two are unpaired. They orbit in a pattern at right angles to one another. These orbits are not spherical but in the shape of a dumbbell.

What is the importance of oxygen atom design and water? A water molecule consists of two hydrogen atoms attached to the oxygen atom in such a way that they pair up with the two unpaired electrons. That means the water molecule is polar in nature with the hydrogen atoms on one end of the molecule and the oxygen atom on the other. The bond angle of the hydrogen atoms would be 90 degrees except for the fact that they repel each other. The repulsion forces the angle out to 105 degrees. This design allows water to have its unique properties which allow life to exist on Earth.

When water freezes, the molecules spread out due to the polar nature of the water molecule. Because of that, ice is lighter than liquid water so lakes freeze on top instead of on the bottom. If lakes froze from the bottom up, life in the water would not be possible. Also because of the polar nature of the water molecule, water dissolves things like salt.

The unique properties of water are due to the design of the oxygen molecule. As a high school chemistry teacher I always enjoy teaching about the oxygen atom design and water. Students are enthralled at the design built into such a simple thing as an oxygen molecule. Almost every time I teach this unit I have some kid say something like, “Wow! Who thought this up?” But this is not the product of a human engineer. An Engineer far wiser than any human created the design of oxygen and built a world that can support life.
–John N. Clayton © 2018
The illustrations are from John N. Clayton’s book The Source: Eternal Design or Infinite Accident? The book goes into much more detail and is available HERE.

Design of Snow Is Awesome

Design of Snow Is Awesome
As I write this, we are sitting here in Michigan after having experienced a record snowfall for one day. As we shovel and snow-blow our driveways and around our mailboxes, we hear a great deal of abusive language from our neighbors. Still, there is a great deal of good in every snowflake because of the design of snow.

It is not just the aesthetic value of snowflakes that makes them good, although that certainly is a wonderful thing to see under a hand lens or microscope. The snow has a variety of other positive attributes designed into its structure.

A snowflake is made of water which is a polar molecule meaning that it has a positive and a negative end. The reason ice forms and water expands as it freezes is that the positive end of one molecule is attracted to the negative end of the next molecule. This structure also allows the snowflake to attract particles in the atmosphere that have a polar makeup. Salt, for example, has a sodium atom which has a plus charge, attracted to chlorine which has a negative charge. A salt molecule in the atmosphere will be attracted to a snowflake. Even molecules such as carbon compounds, which do not generally have a polarity, are attracted to the snowflakes. Snow cleans the air, and many of us enjoy being outside when it is snowing because of the freshness and purity it gives the air.

Snow stores water in places where water shortages are a problem. The western United States gets heavy snow in the mountains in winter. Water has a high heat of fusion. What that means is that it takes extra energy to melt ice–80 calories per gram of ice to be exact. For that reason, snow stays in the solid state for a long time after the temperature has risen above freezing. That allows snow to melt slowly sending a constant supply of water to dry areas at lower elevations.

The design of snow is also friendly to animals, especially small animals. When the snow is finally off the ground here in Michigan, there will be small tunnels visible in the ground where mice, voles, squirrels, and other small animals have built passageways under the snow. The low temperatures of the air in winter are not a problem for these animals because the snow is a good insulator. Predators cannot easily get to the animals because the snow covers them from aerial attacks.

Water is unique in many ways. Its freezing temperature and its boiling temperature are only 100 Celsius degrees apart. That allows water to exist on our planet as a solid, a liquid, and a gas. Each of those states of water allows some form of life to exist.

In Job 38:22 God questions Job, “Have you entered into the treasures of the snow? Or have you seen the treasures of ice which I have reserved against the time of trouble…” The Hebrew word translated “treasure” in this verse is atsar meaning “a thing laid up.” It is doubtful that Job knew anything about the water cycle or how he benefited from snow. But the God who designed snow and its role on Earth to benefit humans and all living things certainly knew all about the design of snow.
–John N. Clayton © 2018
Michigan also has “summer snow”