Arsenic (As) – Periodic Table [Element Information & More]

Arsenic element (As) is in group 15 and period 4 of a periodic table. Arsenic is in the p-block and it is classified as a metalloid on the periodic table.

There is a lot more information related to arsenic which is mentioned in the Information Table given below.

So let’s dive right into it!

Table of contents

• Arsenic element (Information Table)
• Arsenic element in Periodic table
• Facts about Arsenic
• Properties of Arsenic
• Uses of Arsenic

Arsenic Element (Information Table)

The important data related to arsenic element is given in the table below.

Appearance of arsenic	Gray metallic surface
Atomic number of arsenic	33
Symbol of arsenic	As
Atomic mass of arsenic	74.922 u
Protons, Neutrons & Electrons in arsenic	Protons: 33, Neutrons: 42, Electrons: 33
State of arsenic (at STP)	Solid
Group number of arsenic in periodic table	15
Period number of arsenic in periodic table	4
Block of arsenic in periodic table	p-block
Category of arsenic	Metalloids
Bohr model or Electrons per shell or Electrons arrangement in arsenic	2, 8, 18, 5
Electron configuration of arsenic	[Ar] 3d10 4s2 4p3
Orbital diagram of arsenic
Valence electrons in arsenic	5
Electronegativity of arsenic (on pauling scale)	2.18
Atomic radius of arsenic (van der Waals radius)	185 picometers
Density of arsenic	5.73 g/cm3
1st ionization energy of arsenic	9.815 eV
Main isotope of arsenic	75As
Sublimation point of arsenic	887 K or 615 °C or 1137 °F
Crystal structure of arsenic	Rhombohedral

Also see: Interactive Periodic Table (It has rotating bohr models as well as many other details of all the 118 elements in a single periodic table).

Arsenic element in Periodic table

The Arsenic element (As) has the atomic number 33 and is located in group 15 and period 4. Arsenic is a metalloid and it is classified as a pnictogen element.

Click on above elements in the periodic table to see their information.

Facts about arsenic

Here are a few interesting facts about arsenic element.

1. The arsenic element was given its name from the Persian word “Zarnikh” which means “Yellow orpiment”.
2. Arsenic is the 53^rd most abundant element found from the earth’s crust.
3. The arsenic is present in the concentration of 1.8 ppm in the earth’s crust.
4. Arsenic causes damage to skin, nervous system, immune system, excretory system, etc.
5. Pure arsenic is toxic in nature and it was used as poison.
6. Arsenic is mostly found from the igneous rocks on the earth.

Properties of arsenic

Here is a list of some physical properties and chemical properties of arsenic.

Physical properties of arsenic

• At the standard atmospheric pressure, the arsenic transforms directly from solid to gas, which is known as sublimation. And this sublimation temperature is 615 °C.
• Arsenic does not exist in liquid state at standard atmospheric pressure, but it can come to its liquid state at high pressures.
• The density of arsenic is 5.73 g/cm³ and it has an atomic mass of 74.922 u.
• Arsenic has many isotopes including natural as well as radioactive isotopes. Out of these isotopes, the most stable isotope is ⁷⁵As.

Chemical properties of arsenic

• Arsenic is a metalloid and hence it shows the properties of metals as well as nonmetals.
• The electron configuration of arsenic is [Ar] 3d¹⁰ 4s² 4p³, and it has the last electron in p-orbitals. So it is a p-block element.
• If the compounds of arsenic are structured with a hammer, then they release characteristic odor.
• Arsenic gets oxidized when heated in the presence of air. During this reaction, the odor is released which is similar to that of garlic.

Uses of arsenic

Here are some uses of the arsenic element.

• Arsenic is used as an alloying metal with other metals to get harder and durable alloy.
• Grey arsenic is a good conductor of electricity, so it is used in industries.
• Arsenic is also used in preventing the wood degradation that occurs due to termites and fungus.
• Arsenic is also used in transistors as a doping agent.
• Gallium arsenide is used in lasers. When the electric current is passed through gallium arsenide, it produces a light.
• Arsenic is used in the manufacturing of insecticides.

External resources:

1. Arsenic – Element information, properties and uses | Periodic Table. (n.d.). Arsenic – Element Information, Properties and Uses | Periodic Table. https://www.rsc.org/periodic-table/element/33/arsenic
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13. Periodic Table of Elements: Los Alamos National Laboratory. (n.d.). Periodic Table of Elements: Los Alamos National Laboratory. https://periodic.lanl.gov/33.shtml
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