Transcript Noble Gases

Noble Gases
• Argon :1s2 2s2 2p6 3s2 3p6
• Potassium: 1s2 2s2 2p6 3s2 3p6 4s1
• Simplified electron configuration for Argon:
[Ar]
• Simplified electron configuration for
Potassium: [Ar] 4s1
• Noble Gas Simplification
Noble Gas Simplification
• Take the last noble gas before the element of
interest
• Put the noble noble gas we put into the brackets
• Finish the electron configuration for the element
• Example:
– Aluminum: [Ne]3s23p1
– Calcium: [Ar]4s2
Noble Gas Simplification
• This notation for writing electron configurations
helps us to highlight 2 different types of electrons
in the atom
– 1. Electrons in the brackets are called core electrons
• These electrons do not participate in chemical reactions
– 2. The electrons written after the [noble gas] are
called valence electrons
• Valence electrons are those electrons in the highest principal
energy level
• These electrons are important because they are the ones
that are gained, lost or shared in chemical reactions.
Noble Gas Simplification
• Aluminum: [Ne]3s23p1
• This tells us that there are 2 electrons in the 3s orbital and 1
electron in the 3p orbital so aluminum has a total of 3 valence
electrons
• Calcium: [Ar]4s2
– valance electrons: 2
• Manganese: [Ar]4s23d5
– Valance electrons: 2
• Iodine: [Kr]:5s24d105p5
– Valence electrons: 7
Electron Configurations
• Atoms
– Al: 1s2 2s2 2p6 3s2 3p1
• Ions
– Al• Gained an electron
• 1s2 2s2 2p6 3s2 3p2
– Al+
• Lost an electron
• 1s2 2s2 2p6 3s2
– Al3+
• Lost 3 electrons
• 1s2s2p6