Chapter 9: Problem 49
The formation of \(\mathrm{H}_{2}\) from two \(\mathrm{H}\) atoms is an energetically favorable process. Yet statistically there is less than a 100 percent chance that any two \(\mathrm{H}\) atoms will undergo the reaction. Apart from energy considerations, how would you account for this observation based on the electron spins in the two \(\mathrm{H}\) atoms?
Short Answer
Step by step solution
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Hydrogen Atom Bonding
The hydrogen molecule forms because the two electrons occupy a lower energy state when paired. This energy reduction makes the bond formation energetically favorable. Though this process seems straightforward, it's inherently influenced by the characteristics of these electrons and their spins. The way electrons spin plays a pivotal role in determining whether these atoms successfully bond.
Pauli Exclusion Principle
Spin is a fundamental property of electrons, much like charge and mass. It can have one of two orientations: 'up' (+1/2) or 'down' (-1/2). This principle is critical to the bonding process of hydrogen atoms because it necessitates that electrons in a shared orbital must have opposite spins. Thus, during bonding, one hydrogen atom's electron must be 'spin up', while the other atom's electron must be 'spin down'.
- Ensures that each electron in an orbital has a unique spin configuration.
- Drives the spin pairing that enables efficient bonding.
Spin Pairing in Chemistry
In essence, spin pairing reduces repulsion between electrons by ensuring they don't adopt the same spin state when sharing an orbital. The statistical nature of electron spin implies that there's a 50% chance of achieving the correct spin alignment for bonding.
- Facilitates energy-efficient electron sharing.
- Leads to the formation of stable chemical bonds.
- Depends on random distribution of electron spins.