Lead (Pb)
Element 82 · Post-transition metal · atomic mass 207.2 u · group 14, period 6
Electron shells: 2, 8, 18, 32, 18, 4
Lead is soft, dense and easy to work, which is why it was everywhere from Roman plumbing to twentieth-century petrol. Its neurotoxicity, especially in children, ended most of those uses.
Removing lead from petrol produced measurable increases in children's test scores worldwide.
- Atomic number
- 82
- Atomic mass
- 207.2 u
- Electron configuration
- [Xe] 6s² 4f¹⁴ 5d¹⁰ 6p²
- Group · period · block
- 14 · 6 · p
- Oxidation states
- +2, +4
- Electronegativity
- 2.33 (Pauling)
- Melting point
- 327 °C
- Boiling point
- 1,749 °C
- Density
- 11.342 g/cm³
- State at 20 °C
- Solid
- Appearance
- Dull grey metal
- Discovered
- Known since antiquity
82 protons, and 82 electrons when neutral
IUPAC interval [206.14, 207.94]
Carbon group
What Lead is used for
- Lead-acid car batteries
- Radiation shielding
- Soundproofing and ballast
- Historically, pipes, paint and petrol
Atomic structure of Lead
A neutral lead atom has 82 protons and 82 electrons. Its most common isotope carries about 125 neutrons, which is where the mass number 207 comes from. Change the neutron count and you have a different isotope of lead; change the proton count and you have a different element entirely.
Those electrons fill shells from the inside out: 2, 8, 18, 32, 18, 4. In orbital notation that is [Xe] 6s² 4f¹⁴ 5d¹⁰ 6p², leaving 4 valence electrons in the outer shell — the ones that do the chemistry.
3D electron orbitals
See where Lead's electrons actually are — a cloud of 26,000 points sampled from the probability density |ψ|², not a cartoon of a lobe.
Where Lead sits in the periodic table
Metals to the right of the d-block. Softer, lower-melting and more brittle than the transition metals, with more covalent character in their bonding.
Discovery and naming
Lead has been known and used since antiquity, long before anyone could describe it as an element. Its name comes from Old English lead; symbol from Latin plumbum, which is also why its symbol (Pb) does not match its English name.
Keep exploring
Atomic weight from IUPAC/CIAAW; physical properties from PubChem (US National Library of Medicine). Values that have never been measured are shown as “not measured” rather than estimated.
Related Calculators
Frequently Asked Questions
What is the atomic mass of Lead?
The standard atomic weight of Lead is 207.2 u. Because the natural isotope mix varies between sources, IUPAC publishes it as the interval [206.14, 207.94], and 207.2 is the conventional single value to use in calculations.
How many protons, neutrons and electrons does Lead have?
Lead has 82 protons, because the atomic number is the proton count and that is what makes an atom Lead at all. A neutral Lead atom has the same number of electrons, 82. The neutron count varies by isotope; the most common one has about 125, since 207 − 82 = 125.
What is the electron configuration of Lead?
The electron configuration of Lead is [Xe] 6s² 4f¹⁴ 5d¹⁰ 6p². Its electrons are arranged 2, 8, 18, 32, 18, 4 across 6 shells.
Is Lead a metal?
Yes. Lead is classified as a post-transition metal, on the metallic side of the table.
What group and period is Lead in?
Lead is in group 14 (the carbon group), period 6, in the p-block. The group is its column and the period is its row.
What is the charge of Lead?
Lead most commonly forms a 2+ or 4+ ion. It has 4 outer electrons available to lose.
What is the melting point of Lead?
Lead melts at 327 °C and boils at 1,749 °C. That puts it in the solids at everyday temperatures.
What is Lead used for?
Lead-acid car batteries, Radiation shielding, Soundproofing and ballast, Historically, pipes, paint and petrol. Lead is soft, dense and easy to work, which is why it was everywhere from Roman plumbing to twentieth-century petrol.
Who discovered Lead, and where does its name come from?
Lead (Pb) has been known and used since antiquity, long before anyone could describe it as an element. The name comes from Old English lead; symbol from Latin plumbum.