An atom with a formal charge does not necessarily have more or less electron density than the atoms in the molecule without formal charges. We can see this by examining the potential maps for H2O, H3O+, and HO−.
c. Which atom bears the formal positive charge in the hydronium ion? d. Which atom has the least electron density in the hydronium ion?

Verified step by step guidance

1. Identify the structure of the hydronium ion (H3O+). It consists of an oxygen atom bonded to three hydrogen atoms with a positive charge on the oxygen.
2. Determine which atom bears the formal positive charge in the hydronium ion. In H3O+, the oxygen atom has the formal positive charge because it has one more bond than its neutral state.
3. Analyze the electron density in the hydronium ion. The atom with the least electron density will be the one with the highest positive charge.
4. Compare the electron density of the atoms in the hydronium ion. The oxygen atom, bearing the formal positive charge, will have the least electron density.
5. Conclude that in the hydronium ion (H3O+), the oxygen atom bears the formal positive charge and has the least electron density.

Key Concepts

Formal Charge

Formal charge is a theoretical charge assigned to an atom in a molecule, calculated based on the number of valence electrons, the number of bonds, and the number of non-bonding electrons. It helps in understanding the distribution of electrons within a molecule and can indicate the most stable structure. A positive formal charge suggests a deficiency of electrons, while a negative charge indicates an excess.

Electron Density

Electron density refers to the probability of finding electrons in a given region around an atom or molecule. It is visualized using potential maps, where areas of high electron density are typically shown in blue, indicating regions where electrons are more likely to be found. Understanding electron density is crucial for predicting molecular behavior, reactivity, and the nature of chemical bonds.

Potential Maps

Potential maps are graphical representations that illustrate the distribution of electron density in molecules. They provide insights into how electron density varies across different atoms and can highlight regions of positive or negative charge. By analyzing potential maps, one can infer the relative electron density of atoms, which is essential for understanding molecular interactions and reactivity.