Preparation and properties.--Potassium hydrate and calcium hydrate CHAPTER XXII OXIDES OF NITROGEN. Nitrogen monoxide, dioxide, trioxide, tetroaide, pentoxide. CHAPTER XXIII. LAWS OF DEFINITE AND OF MULTIPLE PROPORTION, and their application CHAPTER XXIV. CARBON PROTOXIDE and water gas. CHAPTER XXV. CARBON DIOXIDE. Preparation and tests.--Oxidation in the human system.--Oxidation in water.--Deoxidation in plants CHAPTER XXVI. OZONE. Description, preparation, and test CHAPTER XXVII CHEMISTRY OF THE ATMOSPHERE. Constituents of the air.--Air a mixture.--Water, carbon dioxide, and other ingredients of the atmosphere CHAPTER XXVIII. THE CHEMISTRY OF WATER. Distillation of water.--Three states.--Pure water, sea-water, river-water, spring-water CHAPTER XXIX. THE CHEMISTRY OF FLAME. Candle flame.--Bunsen flame.--Light and heat.--Temperature of combustion.--Oxidizing and reducing flames.--Combustible and supporter.--Explosive mixture of gases.--Generalizations CHAPTER XXX. CHLORINE. Preparation.--Chlorine water.--Bleaching properties.-- Disinfecting power.--A supporter of combustion.--Sources and uses CHAPTER XXXI. BROMINE. Preparation.--Tests.--Description.--Uses CHAPTER XXXII. IODINE. Preparation.--Tests.--Iodo-starch paper.--Occurrence.--Uses.-- Fluorine CHAPTER XXXIII. THE HALOGENS. Comparison.--Acids, oxides, and salts CHAPTER XXXIV. VAPOR DENSITY AND MOLECULAR WEIGHT. Gaseous weights and volumes.--Vapor density defined.--Vapor density of oxygen CHAPTER XXXV. ATOMIC WEIGHT. Definition.--Atomic weight of oxygen.--Molecular symbols.-- Molecular and atomic volumes CHAPTER XXXVI. DIFFUSION AND CONDENSATION OF GASES. Diffusion of gases.--Law of diffusion.--Cause.--Liquefaction and solidification of gases CHAPTER XXXVIL SULPHUR. Separation.--Crystals from fusion.--Allotropy.--Solution.-- Theory of Allotropy.--Occurrence and purification.--Uses.--- Sulphur dioxide CHAPTER XXXVIII. HYDROGEN SULPHIDE. Preparation.--Tests.--Combustion.--Uses.--An analyzer of metals.- -Occurrence and properties CHAPTER XXXIX. PHOSPHORUS. Solution and combustion.--Combustion under water.--Occurrence.-- Sources.--Preparation of phosphates and phosphorus.--- Properties.--Uses.--Matches.--Red phosphorus.---Phosphene CHAPTER XL. ARSENIC. Separation.--Tests.--Expert analysis.--Properties and occurrence.-- Atomic volume.--Uses of arsenic trioxide CHAPTER XLI. SILICON, SILICA, AND SILICATES. Comparison of silicon and carbon.--Silica.--Silicates.--Formation of silica. Chapter XLII GLASS AND POTTERY. Glass an artificial silicate.--Manufacture.--Importance.-- Porcelain and pottery. CHAPTER XLIII. METALS AND THEIR ALLOYS. Comparison of metals and non-metals.--Alloys.--Low fusibility. -- Amalgams CHAPTER XLIV. SODIUM AND ITS COMPOUNDS.