Ionic Compounds: No need to specify the number of ions in the name.
Example: Calcium Chloride implies 1 calcium and 2 chlorides (CaCl₂).
The ratio is determined by common ionic charges to achieve neutrality.
Covalent Compounds
Covalent Compounds: Require specific naming to indicate the number of atoms.
Multiple combinations between two elements can exist.
Example: Carbon and Oxygen can form CO and CO₂, both with different properties.
Binary Molecular Compounds
Binary Molecular Compounds: Formed by non-metals.
Naming conventions:
Name the more metallic element (or the element further left on the periodic table) first.
Name the less metallic element second with the suffix '-ide'.
Use prefixes to indicate the number of atoms:
No prefix for one atom of the first element.
Mono (1) for the second element if it has one atom.
Di (2) for two atoms.
Example: CO is Carbon Monoxide and CO₂ is Carbon Dioxide.
Prefixes for Molecular Naming
Prefixes:
Mono- (1)
Di- (2)
Tri- (3)
Tetra- (4)
Penta- (5)
Hexa- (6)
Hepta- (7)
Octa- (8)
Nona- (9)
Deca- (10)
Special note: If the element name starts with a vowel, the final vowel in a prefix might be dropped (e.g., Dinitrogen Tetroxide instead of Dinitrogen Tetraoxide).
Examples of Naming Compounds
Sulfur Hexafluoride: SF₆
Dinitrogen Tetroxide: N₂O₄
Iodine Heptafluoride: IF₇
Examples of Molecular Formulas from Names
Phosphorus Pentachloride: PCl₅
Carbon Tetrachloride: CCl₄
Dinitrogen Trioxide: N₂O₃
Summary
Understand the fundamental rules for naming both ionic and covalent compounds.
Apply prefixes appropriately based on the number of atoms in the molecule.
Be aware of vowel-dropping when naming compounds with elements that start with vowels.