Ions

• Atoms interact by gaining or losing electrons.

• Ion: An atom or group of atoms that possess an overall charge.

Lithium Example

• Lithium Atom:

  • Protons: 3

  • Electrons: 3

• Lithium Ion:

  • Protons: 3

  • Electrons: 2

  • Net Charge: +1

• Lithium gains or loses electrons to form ions.

Fluorine Example

• Fluorine Atom:

  • Protons: 9

  • Electrons: 9

• Fluoride Ion:

  • Protons: 9

  • Electrons: 10

  • Net Charge: -1

• Like lithium, fluorine also changes its electron count to form ions.

Sulfur and Sulfide Ions

• Sulfur: Atomic number 16

• Common Ion Formed: Sulfide Ion

• Charge of Sulfide Ion: -2

• Electrons in Sulfide Ion:

  • Sulfur atom has 16 protons

  • Sulfide Ion has 18 electrons (16 protons + 2 additional electrons for the charge of -2)

• Overall, 16 protons and 18 electrons in a sulfide ion.