Beryllium (Be) VS Boron (B)
A definitive side-by-side comparison of two essential element profiles.
VS
Main Differences
Beryllium (Be) is an element in the alkaline earth metals category with an atomic number of 4. Boron (B) is an element in the metalloids category with an atomic number of 5.
Boron (B) is 1.3x denser than Beryllium (Be). However, Boron (B) melts at a higher temperature than Beryllium (Be) (a difference of 789.0 Kelvin).
Where do the names come from?
Be Beryllium (Be) Naming History
The name Beryllium is derived from the Greek name for beryl, ''beryllo''.
Boron (B) Naming History
The name Boron is derived from the Arabic 'buraq', which was the name for borax.
Related Comparisons
Compare
Beryllium (Be)
Boron (B)
Category
Alkaline Earth Metals
Metalloids
Atomic Number
4
5
Symbol
Be
B
Atomic Mass
9.012 u
10.81 u
Group
2
13
Period
2
2
Block
s-block
p-block
Standard State (at 20°C)
solid
solid
Density
1.85 g/cm³
2.34 g/cm³
Melting Point (°C)
1287°C
2077°C
Melting Point (°F)
2349°F
3771°F
Melting Point (K)
1560 K
2349 K
Boiling Point (°C)
2468°C
4000°C
Boiling Point (°F)
4474°F
7232°F
Boiling Point (K)
2742 K
4200 K
Year Discovered:
1798
1808
CAS Number
7440-41-7
7440-42-8
Origin of Name:
The name is derived from the Greek name for beryl, ''beryllo''.
The name is derived from the Arabic 'buraq', which was the name for borax.