Chemistry`s Constant Companion TMThe Merck Index is the definitive reference work for scientists and professionals looking for authoritative information on chemicals, drugs and biologicals. The 15th edition is now available from RSC Publishing, in print and online. The Merck Index: Product Description The Merck Index contains over 10,000 monographs with information relating to compounds of significance in research, commerce and environmental impact. The 15th edition, available from Royal Society of Chemistry publishing for the first time, is fully revised and updated.Over 500 new monographs in the 15th edition Over 35% of the existing entries updated Over 10,000 monographs cover more than 18,000 compounds with 50,000 synonymsMolecular weights recalculated with the latest IUPAC standardsNew table showing non-proprietary name stemsRevised Periodic Table and Atomic Weight Tables Free access to The Merck Index OnlineFree one-year access to The Merck Index Online for individual usersFully searchable database of over 11,500 monographsSearchable by structure and sub-structureIncludes historic monographs not available in the print edition  The Merck Index is an essential reference for all scholarly and professional chemists, biochemists, pharmacists and toxicologists and of interest to students, teachers, academic libraries, academic researchers, information professionals, solicitors, journalists and government agencies.