Arsenic is a non-metallic chemical element with symbol At and atomic number 33 that is part of the metalloid family. It is often in its trivalent or pentavalent form and is present in the earth's crust, subsoil and some waters. In its pure state, arsenic is an off-white, grey-yellow, slightly shiny solid. Its solubility is very low in water and very reactive with acids.

Arsenic is very toxic and the fact that trace amounts can be fatal makes it an extremely dangerous natural poison. In the Middle Ages, arsenic was used in the manufacture of patent dyes for home dyeing and is known as "color poison". The toxicity of arsenic has long been recognized and in Europe it was known as the "poison of kings", as many monarchs were thought to have been poisoned with it.

Despite its chloride, arsenic is used as a food additive and implicated in the manufacture of matches, agricultural products such as herbicides and insecticides, and in the treatment of wood. It is also used in the battery industry, electronics and pyrotechnics. Natural arsenic is also used in the semiconductor industry and arsenic compounds are used to make products such as plastics and paints.

613°
613°

74.921595

-3
2
3
5

[Ar] 3d10 4s2 4p3

2
8
18
5

2.18

9.7886

Synthetic

Radioactive

Liquid

Gaseous

Electronic configuration diagram

Characteristics

Name	Arsenic
Number	33
Atomic	74.921595
Symbol	As
Fusion	613
Boiling	613
Density	5.776
Period	4
Group	15

Discovery	1250 Albertus Magnus
Abundance	1.8
Radius	1.3
Electronegativity	2.18
Ionization	9.7886
Number of isotopes	14
Electronic configuration	[Ar] 3d10 4s2 4p3
Oxidation states	-3,2,3,5
Electron by energy level	2,8,18,5

Minerals containing this element : 681

Mineral	Hardness	Density
Abernathyite	2.00 / 3.00	3.31
Adamite	3.50 / 3.50	4.30
Adelite	5.00 / 5.00	3.73
Aerugite	4.00 / 4.00	5.85
Agardite-(Ce)	3.00 / 3.00	3.72
Agardite-(La)	3.00 / 4.00	3.72
Agardite-(Nd)	3.00 / 4.00	3.72
Agardite-(Y)	3.00 / 4.00	3.66
Akrochordite	3.50 / 3.50	3.19
Aktashite	3.50 / 3.50	5.50
Alacránite	1.50 / 1.50	3.40
Alarsite	3.00 / 3.00	3.32
Algodonite	4.00 / 4.00	8.38
Allactite	4.50 / 4.50	3.00
Alloclasite	5.00 / 5.00	6.17
Ambrinoite		3.31
Anduoite	7.00 / 7.00	8.00
Andyrobertsite	3.00 / 3.00	4.01
Angelellite	5.50 / 5.50	4.87
Annabergite	2.00 / 2.00	3.00
Anorpiment	1.50 / 1.50	3.32
Arakiite	3.00 / 4.00
Ardennite-(As)	6.00 / 7.00	3.62
Ardennite-(V)	6.00 / 7.00	3.55
Argentobaumhauerite	3.00 / 3.00	5.31
Argentoliveingite
Argentotennantite	3.50 / 3.50	5.00
Arhbarite
Armangite	4.00 / 4.00	4.43
Arsenbrackebuschite	4.50 / 4.50	6.54
Arsendescloizite	4.00 / 4.00	6.57
Arsenic	3.50 / 3.50	5.70
Arseniopleite	3.50 / 3.50	4.22
Arseniosiderite	1.50 / 1.50	3.50
Arsenoclasite	5.00 / 6.00	4.00
Arsenocrandallite	5.50 / 5.50	3.25
Arsenoflorencite-(Ce)	3.50 / 3.50	4.10
Arsenoflorencite-(La)	3.50 / 3.50	4.10
Arsenoflorencite-(Nd)	3.50 / 3.50	4.05
Arsenogorceixite	4.00 / 4.00	3.65
Arsenogoyazite	4.00 / 4.00	3.33
Arsenohauchecornite	5.50 / 5.50	6.35
Arsenohopeite	3.00 / 3.00
Arsenolamprite	2.00 / 2.00	5.30
Arsenolite	1.50 / 1.50	3.70
Arsenopalladinite	4.00 / 4.00	10.40
Arsenopyrite	5.00 / 5.00	6.07
Arsenovanmeersscheite
Arsenowagnerite
Arsenowaylandite	4.00 / 5.00
Arsenpolybasite	3.00 / 3.00	6.18
Arsenquatrandorite
Arsentsumebite	4.00 / 5.00	6.46
Arsenuranospathite	2.00 / 2.00	2.54
Arsenuranylite	2.50 / 2.50	4.25
Arsiccioite	2.00 / 2.50	5.99
Arsmirandite
Arthurite	3.00 / 4.00	3.02
Asbecasite	6.50 / 7.00	3.70
Asselbornite	3.00 / 3.00
Atelestite	4.50 / 5.00	6.82
Atheneite	5.00 / 5.00	10.20
Attikaite	2.00 / 2.50	3.20
Auriacusite	3.00 / 3.00	4.45
Austinite	4.00 / 4.50	4.13
Babánekite
Barahonaite-(Al)
Barahonaite-(Fe)		3.03
Barikaite		5.34
Bariopharmacoalumite	3.50 / 3.50	2.58
Bariopharmacosiderite	3.00 / 3.00	3.07
Barium-zinc alumopharmocosiderite	2.50 / 2.50
Barrotite
Baumhauerite	3.00 / 3.00	5.33
Baumhauerite II	3.00 / 3.00	5.00
Baumstarkite	2.50 / 2.50	5.33
Bayldonite	4.50 / 4.50	5.50
Bearsite		1.80
Bendadaite
Benleonardite	3.50 / 3.50	7.00
Bergslagite	5.00 / 5.00	3.40
Bernardite	2.00 / 2.00	4.50
Bernarlottiite
Berzeliite	4.50 / 5.00	4.08
Betpakdalite-CaCa	3.00 / 3.00	2.91
Betpakdalite-CaMg	3.50 / 3.50	2.94
Betpakdalite-NaCa		2.89
Betpakdalite-NaNa	3.00 / 3.00	2.88
Bettertonite		2.02
Beudantite	4.00 / 4.00	4.10
Biehlite	1.00 / 1.50
Billingsleyite	2.50 / 2.50	5.90
Bonazziite	2.50 / 2.50	3.54
Borisenkoite
Borishanskiite	4.00 / 4.00	10.00
Boscardinite		3.00
Bouazzerite		2.81
Braccoite		3.56
Bradaczekite