Хафний
72
Hf
Група
4
Период
6
Блок
d
Протони
Електрони
Неутрони
72
72
106
Главни свойства
Атомен номер
72
Атомна маса
178.49
Масов номер
178
Категория
Преходни метали
Цвят
Сив
Радиоактивни
Не
From Hafinia, the Latin name for Copenhagen
Кристална структура
Обикновен шестоъгълник
История
In 1911, Georges Urbain claimed to have found the element in rare-earth residues which was shown later to be a mixture of already discovered lanthanides.
Dirk Coster and George de Hevesy found it by X-ray spectroscopic analysis in Norwegian zircon in 1922.
Anton Eduard van Arkel and Jan Hendrik de Boer were the first to prepare metallic hafnium by passing hafnium tetra-iodide vapor over a heated tungsten filament in 1924.
Dirk Coster and George de Hevesy found it by X-ray spectroscopic analysis in Norwegian zircon in 1922.
Anton Eduard van Arkel and Jan Hendrik de Boer were the first to prepare metallic hafnium by passing hafnium tetra-iodide vapor over a heated tungsten filament in 1924.
Електрон на обвивка
2, 8, 18, 32, 10, 2
Електронна конфигурация
[Xe] 4f14 5d2 6s2
In powdered form, hafnium is pyrophoric and can ignite spontaneously in air
Физични свойства
Фаза
Твърди
Плътност
13.31 g/cm3
Температура на топене
2506.15 K | 2233 °C | 4051.4 °F
Температура на кипене
4876.15 K | 4603 °C | 8317.4 °F
Топлина на сливането
25.5 kJ/mol
Топлина на изпаряване
630 kJ/mol
Специфичен топлинен капацитет
0.144 J/g·K
Изобилие в земната кора
0.00033%
Изобилие в вселената
7×10-8%
Номер на CAS
7440-58-6
Номер на PubChem CID
23986
Атомни свойства
Атомен радиус
159 pm
Ковалентен радиус
175 pm
Електроотрицателност
1.3 (Скала на Полинг)
Йонизационен потенциал
6.8251 eV
Моларен обем
13.6 cm3/mol
Топлопроводимост
0.23 W/cm·K
Оксидационни държави
2, 3, 4
Приложения
Hafnium oxide-based compounds are being introduced into silicon-based chips to produce smaller, more energy efficient and performance packed processors.
Most of the hafnium produced is used in the production of control rods for nuclear reactors.
Hafnium is also used in photographic flash bulbs, light bulb filaments, and in electronic equipment as cathodes and capacitors.
Most of the hafnium produced is used in the production of control rods for nuclear reactors.
Hafnium is also used in photographic flash bulbs, light bulb filaments, and in electronic equipment as cathodes and capacitors.
Hafnium is considered to be non-toxic
Изотопи
Стабилни изотопи
176Hf, 177Hf, 178Hf, 179Hf, 180HfНестабилни изотопи
153Hf, 154Hf, 155Hf, 156Hf, 157Hf, 158Hf, 159Hf, 160Hf, 161Hf, 162Hf, 163Hf, 164Hf, 165Hf, 166Hf, 167Hf, 168Hf, 169Hf, 170Hf, 171Hf, 172Hf, 173Hf, 174Hf, 175Hf, 181Hf, 182Hf, 183Hf, 184Hf, 185Hf, 186Hf, 187Hf, 188Hf