Mo
Molybdenum · element 42
Transition Metal · Solid at room temperature
Molybdenum is a chemical element with symbol Mo and atomic number 42. The name is from Neo-Latin molybdaenum, from Ancient Greek Μόλυβδος molybdos, meaning lead, since its ores were confused with lead ores. Molybdenum minerals have been known throughout history, but the element was discovered (in the sense of differentiating it as a new entity from the mineral salts of other metals) in 1778 by Carl Wilhelm Scheele.
Key facts
Atomic mass
95.951 u
how heavy one atom is
Phase (room temp.)
Solid
Density
10.28 g/cm³
how tightly packed it is
Melting point
2896 K (2623 °C)
when solid turns to liquid
Boiling point
4912 K (4639 °C)
when liquid turns to gas
Period
5
its row in the periodic table
Group
6
its column in the periodic table
Block
D-block
the neighbourhood it lives in
Electronegativity
2.16
how strongly it pulls electrons
Electron configuration
[Kr] 4d5 5s1
where its electrons live
Shells
2 · 8 · 18 · 13 · 1
electrons in each layer, inside to out
Discovered by
Carl Wilhelm Scheele
who found it
Appearance
gray metallic
what it looks like
Source: Wikipedia