Substances with molecular lattices

Molecular lattices are formed by substances with just atomic bonds. A substance with a molecular lattice mostly will be composed of non metals. If a substance contains a metal, in most cases this will have an ionic lattice.
Molecular lattices are found, for example, in: sulphur, with phosphorous, many carbon compounds like saccharides, derivate of benzene, fats, and more.

Possibilities for further research are:
  1. Completely burn the substance (if possible) and see if the lost gases contain Carbon dioxyde and/or watervapor; then you know if the original substance had the elements Carbon and Hydrogen.
  2. You can also try to saponifty the substance with OH-(aq); in case of succes, this indicates an ester or fat.
  3. A positive reaction on Fehlings Reagent or on Tollens reagent indicates the presence of an aldehyde group (for example in a saccharide).

the substance has an ionic lattice

Knowing that a substance has an ionic lattice, then you probable already found if this lattice dissolves in water;
Table XI gives you some indications about certain (im)possibilities.
To find out which ions are present in an unknown substance, you must know and apply a good number of chemical reactions. Separate positive and negative ions can be identified with so called regognition reactions to ions.
It is wise first to research the dry substance, in order to know if ammonium salts or carbonate or sulfides are present.
Also the unknown substance, before the ion research, must be dissolved in water or in acid. For an overview of a number regognitions reactions, please consult a following paragraph.