What is important about ionic radii?
The ionic radius is the measure of an atom’s ion in a crystal structure. As a trend in the periodic table, ionic radii decrease across a period and increase down a group.
Ionic radii are so microscopic that they are difficult to calculate. Measurements can range from 30 pm (0.3 Å) to 200 pm (2 Å) on average. The methods for measuring ionic radii include x-ray crystallography. When electrons are added to an atom, the ion becomes larger than the parent atom and the ionic radius increases. This is because the electron cloud now has the ability to increase in size and the ion can occupy more energy levels. The opposite is true when electrons are removed from an atom.
- In the track and field scenario, how does a decrease in the distance between the runners relate to ionic radii?
- Why are ionic radii important to understand?
- What are the similarities and differences between atomic and ionic radii?