Naming Ionic, Covalent Compounds and Acids

Naming Ionic Compounds:
When naming ionic compounds:

1. write the name of the positive ion element (usually metal)
2. write the name of the negative ion element (usually non-metal) and change the ending to "ide"
3. State the charge of the elements in brackets with roman numerals after the name of the element if has more than one charge

Examples:
FeO = Iron (II) oxide
NaCl = Sodium chloride

Prefixes

Naming Covalent Compounds:

When naming covalent compounds:

1. Write the prefix for the amount of element in the compound
2. Write the name of the first element (do not put prefix "mono" if it's only one for the first element)
3. Write the name of the second element and change the ending to "ide"



Example: 

CO₂ = carbon monoxide

P₂O₅ = diphosphorus pentoxide

CF₄ = carbon tetrafluoride

 

Naming Acids

Acids are always dissolved in water.

HCl is not an acid by itself. When HCl is added to water, a hydronium ion will form (H₃O). This combined with the chlorine ion will form hydrochloric acid.

Rules for Naming Simple Acids:





Lemon is acidic


• Hydrogen is changed into hydro-
• The last syllable in the name of the non-metal is replaced with "ic"
• The word acid is added to the end

Examples:

HF(aq) = hydrofluoric acid

HBr(aq) = hydrobromic acid

Rules For Naming Complex Acids:

• The word hydrogen is completely dropped
• If negative ion ends with "ate" replace it with "ic"
• If negative ino ends with "ite" replace it with "ous"
• add the word "acid" to the end

Examples:

HNO₃(aq) = hydrogen nitrate(compound name)

                 = nitric acid (when dissolved in water)

H₂SO₃(aq) = sulphurous acid



John Dalton



Law of Definite Composition (Proust's Law)

Chemical compounds always have the same proportion of element by mass

Example: C₆H₁₂O₆

Law of Multiple Proportions (Dalton's Law)

Same element can combine in more than one proportion to form different compounds

Example: CO and CO₂