20	Ca	Calcium
Atomic Weight: 40.078				Shells: 2,8,8,2
Group: Alkali Earth Metal				Filling orbital: 4s2
Crystal Structure: Cubic face centered				Covalent radius: 1.74 Å
Oxidation States: +2				Atomic radius: 2.23 Å
Electronegativity, Pauling: 1.00				Atomic volume: 29.9 cm³/mol
State at RT: Solid				First ionization potential: 6.113 V
Melting Point: 1112°K				2nd ionization potential: 11.871 V
Boiling Point: 1757°K				3rd ionization potential: 50.908 V
Density @ 293°K: 1.55 g/cm³				Specific heat: 0.63 J/gK
Electrical conductivity: 0.298 106/cm ohm				Heat of vaporization: 153.60 kJ/mol
Thermal conductivity: 2.00 W/cmK				Heat of fusion: 8.540 kJ/mol
Element Nuclides
Nuclide		Abundance	Weight	Spin	Half-Life	Decay Modes
Ca40		96.97%	39.9626	0		Stable
Ca41		0.%	41.	3.5	1.03E05y
Ca42		0.64%	41.9586	0		Stable
Ca43		0.145%	42.9588	3.5		Stable
Ca44		2.06%	43.9555	0		Stable
Ca45		0.%	44.956	3.5	162.7d	-
Ca46		3.3e-003%	45.9537	0		Stable
Ca47		0.%	46.954	3.5	4.536d	-
Ca48		0.18%	47.9525	0		Stable
Ca49		0.%	49.	1.5	8.72m	-

Name origin: Latin: calx, calcis (lime).
Description: Soft silvery-white metal.
Discovered by: Sir Humphrey Davy
Year: 1808
Location: England
Sources: Obtained from minerals like chalk, limestone & marble. Very abundant. Makes up 3.5% of crust. Occurs only in compounds.
Uses: Used by many forms of life to make shells and bones.

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Registry Numbers

• CAS: 7440-70-2
• RTECS: EV8040000
• DOT: 1855
• NFPA ratings (1-4)
  • Health: 1
  • Flammability: 1
  • Reactivity: 2

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Description
silvery, soft metal, tarnishes to greyish white after exposure to air

Incompatabilities
water acids, air, chlorine, chlorine tri- fluoride, flourine, oxygen, silicon, sulfur

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From DOT Guidebook, Guide Number 37

Fire or Explosion Hazards
Will burn. May ignite itself if exposed to air.
May re-ignite after fire is extinguished. May burn rapidly with flare-burning
effect. Runoff to sewer may create fire or explosion hazard.

Health Hazards
May be harmful if inhaled.
Contact may cause burns to skin and eyes.
Runoff from fire control or dilution water may cause pollution.
Fire may produce irritating or poisonous gases.

Emergency Action: General
Keep unnecessary people away. Stay upwind; keep out of low areas.
Isolate hazard area and deny entry.
Wear self-contained breathing apparatus and full protective clothing.
Also, in case of water pollution call local authorities.
FOR EMERGENCY ASSISTANCE CALL CHEMTREC (800) 424-9300

Emergency Action: Fire
Some of these materials may react violently with water.
SMALL FIRES: Dry chemical, soda ash or lime.
LARGE FIRES: Flood with water from safe distance.
Do not get water inside container. Move container from fire area if you can do
it without risk. Cool containers that are exposed to flames with water from
the side until well after fire is out. For massive fire in cargo area, use
unmanned hose holder or monitor nozzles. If this is impossible, withdraw from
area and let fire burn.

Emergency Action: Spill or Leak
Do not touch spilled material. Stop leak if you can do it without risk.
Do not get water inside containers.
SMALL DRY SPILLS: Flash area with flooding amounts of water.
LARGE SPILLS: Dike for later disposal and dilute with large amounts of water.

Emergency Action: First Aid
Move victim to fresh air; call emergency medical care.
In case of contact with material, immediately flush skin or eyes with running
water for at least 15 minutes. Remove and isolate contaminated clothing and
shoes.

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Material Saftey Data Sheet (MSDS) from OREGON STATE UNIVERSITY

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Return to the Periodic Table