VIII. THE ATMOSPHERE 83 IX. SOLUTIONS 94 X. ACIDS, BASES, AND SALTS; NEUTRALIZATION 106 XI. VALENCE 116 XII. COMPOUNDS OF NITROGEN 122 XIII. REVERSIBLE REACTIONS AND CHEMICAL EQUILIBRIUM 137 XIV. SULPHUR AND ITS COMPOUNDS 143 XV. PERIODIC LAW 165 XVI. THE CHLORINE FAMILY 174 XVII. CARBON AND SOME OF ITS SIMPLER COMPOUNDS 196 XVIII. FLAMES,--ILLUMINANTS 213 XIX. MOLECULAR WEIGHTS, ATOMIC WEIGHTS, FORMULAS 223 XX. THE PHOSPHORUS FAMILY 238 XXI. SILICON, TITANIUM, BORON 257 XXII. THE METALS 267 XXIII. THE ALKALI METALS 274 XXIV. THE ALKALINE-EARTH FAMILY 300 XXV. THE MAGNESIUM FAMILY 316 XXVI. THE ALUMINIUM FAMILY 327 XXVII. THE IRON FAMILY 338 XXVIII. COPPER, MERCURY, AND SILVER 356 XXIX. TIN AND LEAD 370 XXX. MANGANESE AND CHROMIUM 379 XXXI. GOLD AND THE PLATINUM FAMILY 390 XXXII. SOME SIMPLE ORGANIC COMPOUNDS 397 INDEX 421 APPENDIX A Facing back cover APPENDIX B Inside back cover LIST OF FULL-PAGE ILLUSTRATIONS PAGE ANTOINE LAURENT LAVOISIER _Frontispiece_ JOSEPH PRIESTLEY 14 JOHN DALTON 60 WILLIAM RAMSAY 82 DMITRI IVANOVITCH MENDELEEFF 166 HENRI MOISSAN 176 SIR HUMPHRY DAVY 276 ROBERT WILHELM BUNSEN 298 AN ELEMENTARY STUDY OF CHEMISTRY CHAPTER I INTRODUCTION