Overview
This lecture covers Type 1 Binary Ionic Compounds: what they are, how to name them, and how to write their chemical formulas.
What Are Type 1 Binary Ionic Compounds?
- A compound is two or more different elements chemically bonded together.
- "Binary" means the compound contains exactly two different elements.
- "Ionic" refers to a metal bonded to a non-metal.
- "Type 1" means the metal comes from Group 1 or 2 or is silver, zinc, or aluminum.
- Examples: lithium chloride (LiCl), calcium nitride (Ca3N2).
Naming Type 1 Binary Ionic Compounds
- Name the metal first, followed by the non-metal with an "-ide" ending.
- Do not include the charges or the number of atoms in the name.
- Examples:
- BeF2 → beryllium fluoride
- NaCl → sodium chloride
- ZnBr2 → zinc bromide
- Li2O → lithium oxide
- MgS → magnesium sulfide
- Ca3P2 → calcium phosphide
Writing Chemical Formulas from Names
- Write the symbol for the metal and the non-metal.
- Assign their standard ionic charges from the periodic table (Group 1: +1, Group 2: +2, Group 16: -2, Group 17: -1).
- Add subscripts so the total positive and negative charges add up to zero.
- Examples:
- Sodium bromide: Na+ and Br– → NaBr
- Rubidium sulfide: Rb+ and S2– → Rb2S
- Magnesium nitride: Mg2+ and N3– → Mg3N2
- Silver phosphide: Ag+ and P3– → Ag3P
Additional Naming and Formula Examples
- CaF2: calcium fluoride (Ca2+ and F– → CaF2)
- Be3P2: beryllium phosphide (Be2+ and P3– → Be3P2)
- CsF: cesium fluoride
- AlBr3: aluminum bromide
Key Terms & Definitions
- Type 1 Binary Ionic Compound — a compound of a Group 1/2/Ag/Zn/Al metal and a non-metal, with only two elements.
- Ionic Bond — a chemical bond formed by the transfer of electrons from a metal to a non-metal.
- Subscript — a small number in a formula indicating the quantity of atoms.
- -ide Suffix — ending for the non-metal name in ionic compounds.
Action Items / Next Steps
- Complete practice problems: Write formulas for sodium phosphide, name MgO, write formula for strontium fluoride.
- Review periodic table groups and typical ion charges for type 1 metals and non-metals.