Atomic Number
19
Element 19
Potassium (K)
Potassium is a chemical element with symbol K and atomic number 19. It was first isolated from potash, the ashes of plants, from which its name derives.
Atomic Mass
39.098 u
Category
Alkali Metal
Period
4
Group
Group 1: alkali metals and hydrogen
Phase
solid
Density
0.89 g/cm3
Electron Shells
2, 8, 8, 1
Atomic Structure
Protons: 19. Electrons: 19. Neutrons: Varies by isotope.
Electron configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
Why Potassium Matters
Potassium helps connect atomic number 19, alkali metal behavior, period 4 trends, and electron shell structure. Its solid phase, atomic mass of 39.098 u, and electron configuration 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹ make it useful for comparing bonding patterns across the periodic table.
Discovery and Occurrence
Potassium was discovered 1807 by Humphry Davy. Potassium is a chemical element with symbol K and atomic number 19. It was first isolated from potash, the ashes of plants, from which its name derives.
Safety and Handling Context
Potassium is in a highly reactive family. Pure alkali metals can react strongly with water, so demonstrations belong in controlled lab settings.
Related Elements
Frequently Asked Questions
- What is the atomic number of Potassium?
- Potassium has atomic number 19, which means a neutral atom has 19 protons and 19 electrons.
- What is the chemical symbol for Potassium?
- The chemical symbol for Potassium is K.
- What category is Potassium in?
- Potassium is classified as a alkali metal and sits in period 4 of the periodic table.
Explore Potassium in 3D
Use the interactive table above to rotate atomic models, compare periodic trends, and move from Potassium to neighboring elements without losing your place.