How Many Valence Electrons Does Argon Have?

By Staff WriterLast Updated April 05, 2020

Argon has eight valence electrons. Its electron configuration is 1s2 2s2p6 3s2p6, so it has three filled electron shells of 2, 8 and 8. The atomic number of argon is 18.

Argon was discovered by Sir William Ramsay in 1894. It is a nonmetal and a gas at room temperature. Because its outer electron shell is full, it is chemically unreactive. It is a noble gas and belongs to period 3 and group 18 of the periodic table.

Argon has 22 neutrons in its nucleus, and the atomic weight of argon is 39.948 atomic mass units. Its melting point is -308.83 degrees Fahrenheit.