Chemistry
Chemistry is the scientific discipline involved with compounds composed of atoms, i.e. elements, and molecules, i.e. combinations of atoms: their composition, structure, properties, behavior and the changes they undergo during a reaction with other compounds. Chemistry addresses topics such as how atoms and molecules interact via chemical bonds to form new chemical compounds. There are four types of chemical bonds: covalent bonds, in which compounds share one or more electron(s); ionic bonds, in which a compound donates one or more electrons to another compound to produce ions (cations and anions); hydrogen bonds; and Van der Waals force bonds.
Medicinal Chemistry
Medicinal chemistry and pharmaceutical chemistry are disciplines at the intersection of chemistry, especially synthetic organic chemistry, and pharmacology and various other biological specialties, where they are involved with design, chemical synthesis and development for market of pharmaceutical agents, or bio-active molecules (drugs).
Chemistry
The alchemical tradition assumes that every physical art or science is a body of knowledge which exists only because it is ensouled by invisible powers and processes. Physical chemistry, as it is practiced in the modern world, is concerned principally with pharmaceutical or industrial research projects. It is confined within the boundaries of an all-pervading materialism, which binds labor to the advancement of physical objectives.
Manly Palmer Hall (1988) Meditation Symbols in Eastern & Western Mysticism