Naming chemical formula

• Formula


  The combination of symbols which represent the composition and proportions
• Symbol


  Figure with 1,2 or more letters acting as shorthand in place of something
• Oxidation Numbers


  The number of electrons that is apparently lost or gained by an atom in molecular formation
• Rules in Formula Writing

  For ions with same magnitude of charge, write only the formula of the ions

  2. For ions with different magnitude of charge, criss-cross the charges such that the charge of the cation becomes the subscript of the anion and vice-versa but drop the sign

  3. Polyatomic ions carrying a subscript greater than 1 must first be enclosed in parenthesis before the subscript is written
• Binary Compound


  Compounds with two elements, including metals and non-metals, two metals, and polyatomic ions. End at 'ide'.
• Naming


  • CaBr2

  2. Mg3N2

  3. Al2S3

  4. KCl

  5. Na2O
• Binary Ionic Compounds


  Metals with variable oxidation numbers, including transition metals
• Two Methods for Binary Ionic Compounds

  Stock Method: Roman numerals are enclosed with parenthesis

  2. Classical Method: Latin-root 'ous' (lower) and 'ic' (higher)
• Common Cation with Variable Oxidation Numbers

  • Pb+2 (Plumbous, Lead(II))

  Pb+4 (Plumbic, Lead(IV))

  Cu+ (Cuprous, Copper(I))

  Cu+2 (Cupric, Copper(II))

  Fe+2 (Ferrous, Iron(II))

  Fe+3 (Ferric, Iron(III))

  Hg2+2 (Mercurous, Mercury(I))

  Hg+2 (Mercuric, Mercury(II))

  Sn+2 (Stannous, Tin(II))

  Sn+4 (Stannic, Tin(IV))
• Writing Formula and Name


  • Fe+2 and Cl-

  2. Sn+4 and F-

  3. Cu+2 and O-2

  4. Pb+2 and I-

  5. Hg+2 and Br-
• Binary Covalent Compounds


  Two non-metals
• Greek Prefixes


  • mono (1), di (2), tri (3), tetra (4), penta (5), hexa (6), hepta (7), octa (8), nona (9), deca (10)
• Naming


  • NO2

  2. N2O3

  3. PCl4

  4. CS2

  5. CCl4
• Ternary Compounds


  Metals + Polyatomic ions, Hydrogen ions + Polyatomic ions
• Polyatomic Ions


  A group of atoms that carries an overall electric charge
• Formulas and charges of Common Polyatomic Ions

  • Ammonium (NH4+1)

  Nitrite (NO2-1)

  Nitrate (NO3-1)

  Hypochlorite (ClO-1)

  Chlorite (ClO2-1)

  Chlorate (ClO3-1)

  Chromite (CrO2-1)

  Cyanide (CN-1)

  Perchlorate (ClO4-1)

  Hydroxide (OH-1)

  Bicarbonate or Hydrogen Carbonate (HCO3-1)

  Acetate (C2H3O2 or Ac-1)

  Sulfite (SO3-2)

  Sulfate (SO4-2)

  Carbonate (CO3-2)

  Chromate (CrO4-2)

  Dichromite (Cr2O7-2)

  Phosphate (PO4-3)
• Writing Formula


  • Strontium Bicarbonate

  2. Ammonium Nitrate

  3. Iron(III) Sulfate

  4. Copper(II) Carbonate
• Naming


  • K2CrO4

  2. Zn(NO3)2

  3. FeSO4

  4. CuClO3
• Acids


  Formula starts with hydrogen
• Nonoxy Acid


  Binary Acid, H + non-metal, without oxygen. Writing: criss-cross method. Rules: 1. Start with the prefix 'hydro', 2. Add the root of anion, 3. Add the suffix 'is', 4. Add the word 'acid'.
• Naming Nonoxy Acids


  • HBr

  2. HF

  3. HI

  4. HCN
• Oxyacid


  Ternary acids, with oxygen, H+ + Polyatomic ion
• Common Name of Oxyacids

  • Boric Acid (H3BO3, Borate BO3-3)

  Carbonic Acid (H2CO3, Carbonate CO3-2)

  Nitric Acid (HNO3, Nitrate NO3-1)

  Nitrous Acid (HNO2, Nitrite NO2-1)

  Phosphoric Acid (H3PO4, Phosphate PO4-3)

  Phosphorous Acid (H3PO3, Phosphite PO3-3)

  Sulfuric Acid (H2SO4, Sulfate SO4-2)

  Sulfurous Acid (H2SO3, Sulfite SO3-2)

  Perchloric Acid (HClO4, Perchlorate ClO4-1)

  Chloric Acid (HClO3, Chlorate ClO3-1)

  Chlorous Acid (HClO2, Chlorite ClO2-1)

  Hypochlorous Acid (HClO, Hypochlorite ClO-1)

  Permanganic Acid (HMnO4, Permanganate MnO4-1)
• Hydrates


  Substances that contain one or more molecules of water for each formula unit. Upon application of heat, the water is driven off leaving the anhydrous (without water) salt.
• Hydrate Example


  • CuSO4 • 5H2O(S)