Калциум

20
Ca
Група
2
Периода
4
блок
s
Protons
Electrons
Neutrons
20
20
20
Општи Својства
Атомски број
20
Атомска тежина
40,078
Mass Number
40
Category
Земноалкален метал
Color
Silver
Radioactive
Не
From the Latin word calx, lime
Кристална структура
Face Centered Cubic
History
Calcium was known as early as the first century when the Ancient Romans prepared lime as calcium oxide.

Calcium was first isolated by Sir Humphry Davy in 1808 when he electrolyzed a mixture of lime and mercuric oxide.

Davy was trying to isolate calcium; when he heard that Jöns Jakob Berzelius and Pontin prepared calcium amalgam by electrolyzing lime in mercury, he tried it himself.
Electrons per shell
2, 8, 8, 2
Електронска конфигурација
[Ar] 4s2
Ca
The shell of an egg is made up of primarily calcium carbonate
Физички Својства
Фаза
Solid
Густина
1,54 g/cm3
Точка на топење
1115,15 K | 842 °C | 1547,6 °F
Точка на вриење
1757,15 K | 1484 °C | 2703,2 °F
Топлина на топење
8,54 kJ/mol
Топлина на испарување
155 kJ/mol
Specific Heat Capacity
0,647 J/g·K
Abundance in Earth's crust
5%
Abundance in Universe
0,007%
Pure
Кредити на слика: Wikimedia Commons (Matthias Zepper)
Pure calcium in a protective argon gas atmosphere
CAS Number
7440-70-2
PubChem CID Number
5460341
Атомски Својства
Атомски полупречник
197 pm
Ковалентен полупречник
176 pm
Електронегативност
1,00 (Полингова скала)
Ionization Potential
6,1132 eV
Atomic Volume
29,9 cm3/mol
Thermal Conductivity
2,01 W/cm·K
Oxidation States
1, 2
Applications
Calcium is used to remove oxygen, sulfur and carbon from alloys.

It is also used as an alloying agent used in the production of aluminum, beryllium, copper, lead, and magnesium alloys.

Calcium is used as a reducing agent in the extraction of other metals, such as uranium, zirconium, and thorium.

Calcium carbonate is used in manufacturing cement and mortar, lime and limestone.
Calcium is considered to be non-toxic
Isotopes
Stable Isotopes
40Ca, 42Ca, 43Ca, 44Ca, 46Ca
Unstable Isotopes
34Ca, 35Ca, 36Ca, 37Ca, 38Ca, 39Ca, 41Ca, 45Ca, 47Ca, 48Ca, 49Ca, 50Ca, 51Ca, 52Ca, 53Ca, 54Ca, 55Ca, 56Ca, 57Ca