Potassium is a soft silvery metal that reacts rapidly with atmospheric oxygen.
Core Principles & Analysis
Humphry Davy isolated potassium from molten potash in 1807, making it the first metal ever obtained by electrolysis.
The soft metal reacts with water so vigorously that the liberated hydrogen ignites, and it tints flames lilac; natural potassium-40 makes bananas measurably radioactive.
About 95% of potassium production goes into fertilizers, and potassium ions are essential for nerve impulses and heart rhythm in the human body.