Inorganic Nomenclature By Prem D Sattsangi Christopher L

Bite size chemistry for your mind Click here to go back to the beginning at any time.

Introduction (Writing Formulae, a dynamic process)

1. What is an ionic compound? It contains Cation, Anion, and has no charge. Cation (Ion with positive charge) e. g. Na+ Anion (Ion with negative charge) e. g. Cl- no charge: total charge(s) on Cation equal total charge(s) on Anion.

2. Three Steps to writing Formula 1. Cations: E. g. Formula and charge Ammonium (NH 4+ ), 2. Anions: E. g. Formula and charge Phosphate (PO 43 - ) 3. Compound: Equalize charges on Ions 3 NH 4+ + PO 43 - (NH 4)3 PO 4

3. Building blocks of formulae IN THIS TUTORIAL • Yellow blocks represent positive charges, +1, +2, +3. • Pink blocks represent negative charges, -1, -2, -3. Positive and negative charges must be equal in a compound.

4. Periodic Table Group (A) No. and the charges For metals, Group (A)No. = No. of Positive charges Gr. (A)No. Charge E. G. 1 2 3 +1 +2 +3 Na+ Ca 2+ Al 3+ Blocks (3 sizes) For non-metals, Group (A)No. – 8 = No. of Negative charges 5 -8 6 -8 7 -8 -3 -2 -1 N 3 O 2 Cl-

Section-1 Cations

1. 1. Names for Cations Simple Cations “same as the element” Al 3+ aluminum Ca 2+ calcium K+ potassium

1. 2. Names of Transition Metal Cations and Ammonium ion Many transition metals e. g. Cr, Fe, Cu, Mn, Au… form Cations with different charges. Name includes (Charge). • • Name Copper(I) Copper(II) Iron(III) Formula Blocks Cu+ Cu 2+ Fe 3+ • Ammonium NH 4+ (polyatomic)

Section-2 Anions

2. 1. Names for Anions. Simple Anions end in –ide. O 2 - oxide Cl- chloride Oxyanions, only, end in –ite, or –ate. NO 2 - nitrite NO 3 - nitrate

2. 2. Polyatomic anions ( -ide) Oxyanions( –ite, -ate) POLYATOMIC ANIONS (End in -ide) Name Formula Block Hydroxide OHCyanide CNOXYANIONS: (End in –ite, -ate) Hypochlorite Cl. OChlorite Cl. O 2 Chlorate Cl. O 3 Perchlorate Cl. O 4 -

2. 3. Remembering Oxyanions Oxyanion nonmetal oxygen Formula Carbonate “C” “O” CO 32 - Nitrate “N” “O” NO 3 - “O” Cl. O 3 - Chlorate “Cl” Phosphate “P” “O” PO 43 - Sulphate “S” “O” SO 42 - IV V VI CO 32 - NO 3 PO 43 - SO 42 - Cl. O 3 Keep writing in this section of Periodic table. Acetate is an organic anion, “C 2 H 3 O 2 -” need be memorized. Memorize: charges: -3, -2, -1 Left right and subscript on “O”: 3, 3, 3, 4, 4 Top bottom VII

2. 4. Polyatomic Ions ending in “ –ite” have one less oxygen… “ –ite” or “ -ate” CHARGE REMAINS UNCHANGED -ite takes a BITE of “O” to become -ate Phosphite, PO 33 - + O PO 43 - , phosphate Sulfite, SO 32 - + O SO 42 - , sulfate chlorite, Cl. O 2 - + O Cl. O 3 - , chlorate nitrite, NO 2 - + O NO 3 - , nitrate

2. 5. Polyatomic anions memorize POLYATOMIC ANIONS 1. hydroxide cyanide chlorate nitrate acetate = OH= CN= Cl. O 3= NO 3= C 2 H 3 O 2 - 2. sulfate = SO 42 carbonate = CO 32 - Only 2 3. phosphate = PO 43 - Only 1

Section-3 Compounds

3. 1. Balancing Charges Sodium Ion “Na+” has one positive charge. Na+ Chloride Ion “Cl-” has one negative charge. Cl- So the building blocks of Na+ and Cl- combine together with no adjustments needed. Na. Cl = sodium chloride The positive and negative charges are equal. CORRECT COMBINATION

3. 2. Which combinations are correct? (click mouse button to see. ) 1. 2. 3. 4. 5. 6. 7. 8. 9.

3. 3. Variety of correct C: A combinations.

3. 4. When charges are equal no adjustments are needed. 1. Na+ + Cl- Na. Cl 5. Ca 2+ + O 2 - Ca. O 9. Al 3+ Al. N + N 3 -

3. 5. Unequal charges need be adjusted. Sodium Ion “Na+” has one positive charge. Oxide Ion “O 2 -” has two negative charges. Na+ + O 2 - “Na. O” is not correct. Na+ and O 2 - have unequal charges. It would take two single Na+ charges to combine with one O 2 - charge. Na 2 O = sodium oxide

3. 6. A short cut, is to make the CHARGE (superscript) on one element as the subscript of the other. Na+ O 2 - + Na 2 O Try it yourself now. Combine Na+ and N 3 -. Hint: (Click mouse button to reveal answer. ) Answer: Na+ N 3 - Na 3 N = sodium nitride

Section-4 Acids [ n. H+ + Anions Acids ]

4. 1. All ACIDS contain “Hydrogen” Ion and NO Charge “H+” + “Anion” Acid Name of Acid Formula Corresponding Hydrochloric H+ + Cl- HCl “–ous” acids Acetic H+ + C 2 H 3 O 2 - HC 2 H 3 O 2 *Nitric H+ + NO 3 - HNO 3 *Chloric H+ + Cl. O 3 - HCl. O 3 *Sulfuric 2 H+ + SO 42 - H 2 SO 4 *Phosphoric 3 H+ + PO 43 - H 3 PO 4 (-O) All Acid names here end in “–ic” Corresponding (-O) acids, end in “–ous” HNO 2 HCl. O 2

4. 2. Related anions and acids (No Charge) Each H+ reduces one negative charge. Phosphate ion Hydrogenphosphate ion PO 43 - HPO 42 Dihydrogenphosphate ion H 2 PO 4 - Acids have no charge. Ending -ate is changed to -ic acid. Phosphoric acid H 3 PO 4

4. 3. Related anions and acids Sulphate ion Hydrogensulphate ion SO 42 - HSO 4 - Acids have no charge. Ending -ate is changed to -ic acid. Sulphuric acid H 2 SO 4

4. 4. Related anions and acids Carbonate ion Hydrogencarbonate ion CO 32 - HCO 3 - Acids have no charge. Ending -ate is changed to -ic acid. Carbonic acid H 2 CO 3

Section-5 Bases [ Cations + n. OH- Bases ]

5. 1. Common Bases (Hydroxides) • sodium Ion “Na+” and Hydroxide Ion “OH-” Na+ + OH- Na. OH = sodium hydroxide • Potassium Ion “K+” and Hydroxide Ion “OH-” • K+ + OH- KOH = potassium hydroxide • Magnesium Ion “Mg 2+” and Hydroxide Ion “OH-” • Mg 2+ + OH- Mg(OH)2 = magnesium hydroxide • Ammonium Ion “NH 4+” and Hydroxide Ion “OH-” • NH 4+ + OH- NH 4+OH = ammonium hydroxide

5. 2. Congratulations, you’ve just completed Bases, and have finished this online tutorial. Online School of Learnin g Virtual Diploma

Acknowledgements • * Prem D. Sattsangi – Summer Research Stipend and – Financial Support from Eberly Science Fund • # Christopher L. Byers – Undergraduate Research Fund – Federal Work-Study Grant