Dr. Glaser's "Chemistry is in the News"
To Accompany Bruice, Organic Chemistry, 3/e.
Chapter 3. Reactions of Alkenes. Thermodynamics and Kinetics.

Editorial Comments

There are many theories as to what it takes to create life on our home planet or on any other planet. In fact, it does not even have to be a planet; a nice moon would do just fine. Let's look at some of the chemical aspects of the Origin of Life.

Charles Darwin presented us with the breath-taking idea of evolution, the idea that all life, however complex, might have evolved from the conditions "in some warm little pond". The Earth's oceans are considered as the primordial pool that brought together water and simple chemicals, heat, and light to allow for chemical reactions that might - in the course of eons - lead to the formation of more complexity in the arsenal of chemicals and, perhaps, even to the formation of simple organisms.

The Miller experiment was a very important one. The experiments were actually conducted by Stanley Miller and Harold Urey and they involved the study of the reactions products obtained when a gas mixture of water, hydrogen, methane and ammonia is exposed to lightning. This simple setup actually produces quite a few organic molecules and even some amino acids. Since amino acids are the basic components of proteins, these experiments suggested that some of the organic molecules that occur in living organism are actually easy to come by.

Deep sea vents have recently attracted considerable attention. Did deep sea vents produce the energy that helped to create the first life forms? Perhaps these deep sea vents are a more realistic alternative to the "warm little pond"?

In this context, the hypothesis has generated much recent excitement as to whether the Jovian moon Europa might potentially be another life-bearing "rock" in the solar system.

Questions

Question 1: What gases are present in the atmosphere of the Jovian moon Europa? Would the "Miller experiment" produce any amino acids in Europa's atmosphere?

Answer 1: No. Europa's atmosphere contains only hydrogen and carbon dioxide. The Miller experiment requires methane, ammonia and water to form amino acids.

Question 2: What geological feature makes the Jovian moon Europa so unique, and potentially life-bearing among the planetary moon in the solar system?

Answer 2: The existence of a warm global ocean of water deep beneath the surface ice.

Question 3: Jupiter is the fifth planet from the sun and over 5 times farther away from the sun than Earth. Where is the heat on Europa coming from?

Answer 3: Core of molten metal and deep sea volcanoes.

Question 4: Using your knowledge of thermodynamics and kinetics, explain why the existence of a "warm ocean of water" is thought to be a prerequisite for chemical genesis.

Answer 4: Even if thermodynamics are in favor of a reaction to occur, the rate of reaction depends on the reaction rate constant and on the concentrations of the reagents. According to Arrhenius, rate constants depend on the temperature. High concentrations are more easily achieved in the liquid phase (an ocean for example) than in the gas phase (an atmosphere).

Chemistry & Genesis.
Question 5: This question is meant to start a discussion. Perhaps you can discuss this question with your peers (i.e. on the course discussion list). Here is the question: Given what is now known about the observed universe, is is reasonable to assume that Earth is the only place in the universe that has produced genesis? Similary, is is reasonable to assume that our solar system or our Milky Way galaxy are the only places in the universe that has produced genesis?