Question

Study these 27 compounds and try to group them based on their similarities. There are nine main types with three examples in each group. Organize these 27 into the following groups: Acid (binary or ternary); organic; molecular; hydrated salts; Ionic (binary and ternary) Should be in 7 groups and why are they in the group

			Na3PO4⋅12H2O   sodium phosphate dodecahydrate Ca2C                    Calcium Carbide                                        Fe(OH)2                 iron(II) hydroxide PCl3                     Phosphorus trichloride CuSO4⋅5H2O        copper(II) sulfate pentahydrate HgBr2           mercury (II) bromide N2O5                 Dinitrogen Pentoxide AlCl3⋅6H2O        aluminum chloride hexahydrate NH4ClO2             Ammonium chlorite                       HCl (aq)       hydrochloric acid LiH                  Lithium hydride Sn(Cr2O7)2       tin(IV) dichromate H2CO3 (aq)       carbonic acid Co(NO3)2⋅6H2O    cobalt(II) nitrate hexahydrate KMnO4             Potassium permanganate C5H10       pentene Cu3N            Copper(I) Nitride CCl4                  Carbon Tetrachloride PbSO4                   lead(II) Sulfate Mg(ClO3)2⋅6H2O magnesium chlorate hexahydrate C8H18       octane H2SO3 (aq)         sulfurous acid Ba3P2                  Barium phosphide LiCN                 Lithium Cyanide PbO2       Lead (IV) oxide C2H5OH       ethanol CuCl2⋅2H2O             copper(II) chloride dihydrate

Develop a set of rules that help you identify ionic, acid, hydrated, molecular and organic compounds.   

Answer 1

1) Binary acid

These compounds are compounds containing two elements. Binary acids containing hydrogen (H) with another element.

HCl (aq) – hydrochloric acid

2) Ternary acid

These compounds are compounds containing three elements. Ternary acids containing hydrogen (H) with two elements.

H₂CO₃ (aq) – carbonic acid

H₂SO₃ (aq) – sulfurous acid

3) Organic compound

Organic compounds are compounds containing carbon, hydrogen and other elements.

C₅H₁₀ – pentene

C₈H₁₈ – octane

C₂H₅OH – ethanol

4) Molecular compound

Molecular compounds are compounds that are composed of covalent bonds and do not ionize in aqueous solutions.

PCl₃ – phosphorus trichloride

N₂O₅ – dinitrogen pentoxide

CCl₄ – carbon tetrachloride

5) Hydrated salts – hexahydrates

Hydrated salts contain water of crystallization in the molecular structure. Hexahydrated salts contain 6 molecules of water of crystallization.

AlCl₃.6H₂O – aluminum chloride hexahydrate

Co(NO₃)₂.6H₂O – cobalt (II) nitrate hexahydrate

Mg(ClO₃)₂.6H₂O – magnesium chlorate hexahydrate

6) Hydrated salts – contains other than 6 molecules of water

This group includes di, penta and dodecahydrates.

CuCl₂.2H₂O

CuSO₄.5H₂O

Na₃PO₄.12H₂O

7) Binary ionic salts of alkali and alkaline earth metals

Ionic salts are composed of ions and ionize in aqueous solutions. Binary ionic salt contain only two elements – a metal and a non-metal. The metal belongs to groups I or II of the periodic table.

CaC₂ – calcium carbide

LiH – lithium hydride

Ba₃P₂ – barium phosphide

8) Binary ionic salts of transition metals

The metal ion is a transition metal in these salts.

HgBr₂ – mercury (II) bromide

Cu₃N – copper (I) nitride

PbO₂ – lead (II) oxide

9) Ternary ionic salts

These are ionic salts containing three elements.

Fe(OH)₂ – iron (II) oxide

NH₄ClO₂ – ammonium chlorite

Sn(Cr₂O₇)₂ – tin (II) dichromate

KMnO₄ – potassium permanganate

PbSO₄ – lead (II) sulfate

LiCN – lithium cyanide