Boron

5
B
Golongan
13
Periode
2
Blok
p
Proton
Elektron
Neutron
5
5
6
Sifat Umum
Nomor atom
5
Massa atom
10,811
Nomor massa
11
Kategori
Metaloid
Warna
Hitam
Radioaktif
Tidak
Dari kata Arab Buraq dan kata Persia Burah
Struktur kristal
Trigonal Sederhana
Sejarah
Boron compounds have been known for thousands of years, but the element was not discovered until 1808 by Sir Humphry Davy and by Gay-Lussac and Thenard.

Boron was not recognized as an element until it was isolated in 1808 by Sir Humphry Davy and by Joseph Louis Gay-Lussac and Louis Jacques Thénard.

Jöns Jakob Berzelius identified boron as an element in 1824.
Elektron per kulit
2, 3
Konfigurasi elektron
[He] 2s2 2p1
B
Boron is an essential nutrient for all green plants
Sifat Fisika
Fase
Solid
Kepadatan
2,34 g/cm3
Titik lebur
2349,15 K | 2076 °C | 3768,8 °F
Titik didih
4200,15 K | 3927 °C | 7100,6 °F
Kalor peleburan
50 kJ/mol
Kalor penguapan
507 kJ/mol
Kapasitas kalor molar
1,026 J/g·K
Kelimpahan di kerak bumi
0,00086%
Kelimpahan di alam semesta
1×10-7%
Pure
Kredit Gambar: Images-of-elements
Pure crystalline boron, front side
Nomor CAS
7440-42-8
PubChem CID Number
5462311
Sifat Atom
Jari-jari atom
90 pm
Jari-jari kovalen
84 pm
Elektronegativitas
2,04 (Skala Pauling)
Potensi Ionisasi
8,298 eV
Volume atom
4,6 cm3/mol
Kondusivitas termal
0,274 W/cm·K
Bilangan oksidasi
1, 2, 3
Aplikasi
Boron oxide is used in glassmaking and ceramics.

Borax is used in making fiberglass, as a cleansing fluid, a water softener, insecticide, herbicide and disinfectant.

Boric acid is used as a mild antiseptic and as a flame retardant.

Boron shielding is used as a control for nuclear reactors.
Elemental boron, boron oxide, boric acid, borates and many organoboron compounds are non-toxic
Isotop
Isotop stabil
10B, 11B
Isotop tidak stabil
7B, 8B, 9B, 12B, 13B, 14B, 15B, 16B, 17B, 18B, 19B