Ions

Positive ions are called cations.

This air cleaner came pretty cheap when I bought it, but I'm rather suspicious of the "negative ions" it produces.

This is a reaction where charges are transferred by the insertion of ions into a solid host.

Inside the magnetosphere, the density of the space plasma—charged particles, like electrons and ions—is much lower than the plasma outside, where the solar wind prevails. The boundary, called the magnetopause, becomes unstable when the two different density regions move at different rates.

Inside the magnetosphere, the density of the space plasma — charged particles, like electrons and ions — is much lower than the plasma outside, where the solar wind prevails. The boundary, called the magnetopause, becomes unstable when the two different density regions move at different rates. Giant swirls, called Kelvin Helmholtz waves, form along the edge like crashing ocean waves.

Far from being an empty void, the space around Earth is a jungle of invisible fields and tiny particles. It’s draped with twisted magnetic field lines and swooping electrons and ions.

Earth’s magnetic environment traps electrons and ions in concentric belts encircling the planet. These belts, called the Van Allen Radiation Belts, keep most of the high-energy particles at bay.

When CO₂ is absorbed by seawater, a series of chemical reactions occur resulting in the increased concentration of hydrogen ions. This increase causes the seawater to become more acidic and causes carbonate ions to be relatively less abundant.

Decreases in carbonate ions can make building and maintaining shells and other calcium carbonate structures difficult for calcifying organisms such as oysters, clams, sea urchins, shallow water corals, deep sea corals, and calcareous plankton.

When dropped in water, silver ions, which are atoms that have an electrical charge, are released to purify the water.