Hf - Hafnium

The transition element hafnium was discovered by Coster and Hevesey in 1923 in Denmark.

Atomic number - 72 Density g/mL 13 .1

Atomic weight u 178 .49 Melting point K 2500

Bonding radius A 1 .44 Boiling point K 4876

Atomic radius A 2 .16 Heat of vaporization kJ/mol 575

Ionization Potential V 6 .65 Heat of fusion kJ/mol 24 .06

Electronegativity - 1 .3 Specific heat J/gK 0 .14

The oxide is amphoteric.
Crystal are hexagonal.

Electron config. : [Xe] 4f¹⁴ 5d² 6s²

Isotopes of Hf: Click mass number for decay process, product for element page.

154 2 sec a/EC,6.700 Yb-150/Lu-154 153.96425	155 0.89 sec a/EC,8.000 Yb-151/Lu-155 154.96274	156 25 msec a,6.033 MeV Yb-152 155.95920	157 110 msec a/EC,5.880 Yb-153/Lu-157 156.95813	158 2.86 sec a/EC,5.100 Yb-154/Lu-158 157.95464	159 5.6 sec a/EC,6.700 Yb-155/Lu-159 158.95383	160 13.6 sec a/EC,4.370 Yb-156/Lu-160 159.95071
161 16.8 sec a/EC,6.300 Yb-157/Lu-161 160.95032	162 37.6 sec a/EC,3.450 Yb-158/Lu-162 161.94720	163 40.0 sec EC,5.500 MeV Lu-163 162.94707	164 111 sec EC,2.970 MeV Lu-164 163.94442	165 76 sec EC,4.600 MeV Lu-165 164.94449	166 6.77 min EC,2.300 MeV Lu-166 165.94224	167 2.05 min EC,4.000 MeV Lu-167 166.94259
168 25.95 min EC,1.800 MeV Lu-168 167.94063	169 3.24 min EC,3.270 MeV Lu-169 168.94115	170 16.01 hr EC,1.100 MeV Lu-170 169.93964	171 12.1 hr EC,2.400 MeV Lu-171 170.94049	172 1.87 yr EC,8.600 MeV Lu-172 171.93946	173 23.6 hr EC,1.610 MeV Lu-173 172.94065	174 0.162% 2.0E15 yr a,2.495 MeV Yb-170 173.94004
175 70 da EC,6.782 MeV Lu-175 174.94150	176 5.206% Stable 175.94140	177 18.606% Stable 176.94322	178 27.297% Stable 177.94369	179 13.629% Stable 178.94581	180 35.100% B-Stable Ta-180 179.94654	181 42.39 da B-,1.027 MeV Ta-181 180.94909
182 9E+6 yr B-,9.300 MeV Ta-182 181.95055	183 1.067 hr B-,2.010 MeV Ta-183 182.95352	184 4.12 hr B-,1.340 MeV Ta-184 183.95544	184a 48 sec B-,1.340 MeV Ta-184 183.95544	185 3.5 min B-,6.000 MeV Ta-185 184.95902	MASS abund. Halflife Particle, Energy Decay Product(s) Isotopic Mass

Atomic number	-	72		Density	g/mL	13	.1
Atomic weight	u	178	.49	Melting point	K	2500
Bonding radius	A	1	.44	Boiling point	K	4876
Atomic radius	A	2	.16	Heat of vaporization	kJ/mol	575
Ionization Potential	V	6	.65	Heat of fusion	kJ/mol	24	.06
Electronegativity	-	1	.3	Specific heat	J/gK	0	.14
The oxide is amphoteric.				Crystal are hexagonal.
Electron config. : [Xe] 4f¹⁴ 5d² 6s²