Aqua fortis
Encyclopedia
Aqua fortis, or "strong water," in alchemy
, is a solution
of nitric acid
(HNO3) in water
. Being highly corrosive
, the solution was used in alchemy for dissolving silver
and most other metals with the notable exception of gold
, which can only be dissolved using aqua regia
. Aqua fortis was prepared by mixing either sand, alum
, or vitriol
, or the last two together, with saltpeter
, then distilling it by a hot fire. The gas collected from this condenses into aqua fortis. It was first described by alchemist Pseudo-Geber
.
Aqua fortis was useful to refiners for parting or separating silver from gold and copper
; to the workers in mosaic
for staining and coloring their woods; to other artists for coloring of bone and ivory, which is done by tinging the items with copper
or verdigris
, then soaking in aqua fortis. Some also turn it into aqua regia
, by dissolving in a quarter of its weight of sal ammoniac
, and then use this to stain ivory and bone, of a fine purple color. Book binders also put it on leather, making fine marble covers for books. Diamond cutters used it to separate diamonds from metalline powders. It was also used in etching copper or brass
plates. It was mixed with oil of vitriol and used to stain cane
s to appear like a tortoise shell by applying several coats while the cane is over hot coals. The canes were then given a gloss with a little soft wax and a dry cloth. Liquor ammonia fortis is a saturated solution of ammonia in water. It is called 880 ammonia. It has a relative density of 0.880. It is stored in tightly stoppered bottles in a cold place.Concise Chemistry Class X
Alchemy
Alchemy is an influential philosophical tradition whose early practitioners’ claims to profound powers were known from antiquity. The defining objectives of alchemy are varied; these include the creation of the fabled philosopher's stone possessing powers including the capability of turning base...
, is a solution
Solution
In chemistry, a solution is a homogeneous mixture composed of only one phase. In such a mixture, a solute is dissolved in another substance, known as a solvent. The solvent does the dissolving.- Types of solutions :...
of nitric acid
Nitric acid
Nitric acid , also known as aqua fortis and spirit of nitre, is a highly corrosive and toxic strong acid.Colorless when pure, older samples tend to acquire a yellow cast due to the accumulation of oxides of nitrogen. If the solution contains more than 86% nitric acid, it is referred to as fuming...
(HNO3) in water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
. Being highly corrosive
Corrosive
A corrosive substance is one that will destroy or irreversibly damage another surface or substance with which it comes into contact. The main hazards to people include damage to the eyes, the skin, and the tissue under the skin; inhalation or ingestion of a corrosive substance can damage the...
, the solution was used in alchemy for dissolving silver
Silver
Silver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...
and most other metals with the notable exception of gold
Gold
Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...
, which can only be dissolved using aqua regia
Aqua regia
Aqua regia or aqua regis is a highly corrosive mixture of acids, fuming yellow or red solution, also called nitro-hydrochloric acid. The mixture is formed by freshly mixing concentrated nitric acid and hydrochloric acid, usually in a volume ratio of 1:3, respectively...
. Aqua fortis was prepared by mixing either sand, alum
Alum
Alum is both a specific chemical compound and a class of chemical compounds. The specific compound is the hydrated potassium aluminium sulfate with the formula KAl2.12H2O. The wider class of compounds known as alums have the related empirical formula, AB2.12H2O.-Chemical properties:Alums are...
, or vitriol
Sulfuric acid
Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...
, or the last two together, with saltpeter
Saltpeter
Saltpeter or saltpetre often refers to:*Potassium nitrate, or the mineral niter, the critical oxidizing component of gunpowder, and a food preservative.It may also refer to:...
, then distilling it by a hot fire. The gas collected from this condenses into aqua fortis. It was first described by alchemist Pseudo-Geber
Pseudo-Geber
Pseudo-Geber is the name assigned by modern scholars to an anonymous European alchemist born in the 13th century, sometimes identified with Paul of Taranto, who wrote books on alchemy and metallurgy, in Latin, under the pen name of "Geber". "Geber" is the shortened and Latinised form of the name...
.
Aqua fortis was useful to refiners for parting or separating silver from gold and copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
; to the workers in mosaic
Mosaic
Mosaic is the art of creating images with an assemblage of small pieces of colored glass, stone, or other materials. It may be a technique of decorative art, an aspect of interior decoration, or of cultural and spiritual significance as in a cathedral...
for staining and coloring their woods; to other artists for coloring of bone and ivory, which is done by tinging the items with copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
or verdigris
Verdigris
Verdigris is the common name for a green pigment obtained through the application of acetic acid to copper plates or the natural patina formed when copper, brass or bronze is weathered and exposed to air or seawater over a period of time. It is usually a basic copper carbonate, but near the sea...
, then soaking in aqua fortis. Some also turn it into aqua regia
Aqua regia
Aqua regia or aqua regis is a highly corrosive mixture of acids, fuming yellow or red solution, also called nitro-hydrochloric acid. The mixture is formed by freshly mixing concentrated nitric acid and hydrochloric acid, usually in a volume ratio of 1:3, respectively...
, by dissolving in a quarter of its weight of sal ammoniac
Sal ammoniac
Sal ammoniac is a rare mineral composed of ammonium chloride, NH4Cl. It forms colorless to white to yellow-brown crystals in the isometric-hexoctahedral class. It has very poor cleavage and a brittle to conchoidal fracture. It is quite soft, with a Mohs hardness of 1.5 to 2, and has a low specific...
, and then use this to stain ivory and bone, of a fine purple color. Book binders also put it on leather, making fine marble covers for books. Diamond cutters used it to separate diamonds from metalline powders. It was also used in etching copper or brass
Brass
Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties.In comparison, bronze is principally an alloy of copper and tin...
plates. It was mixed with oil of vitriol and used to stain cane
Cane
Cane are either of two genera of tall, perennial grasses with flexible, woody stalks from the family Poaceae that grow throughout the world in wet soils. They are related to and may include species of bamboo. The genus Arundo is native from the Mediterranean region to the Far East. Arundinaria...
s to appear like a tortoise shell by applying several coats while the cane is over hot coals. The canes were then given a gloss with a little soft wax and a dry cloth. Liquor ammonia fortis is a saturated solution of ammonia in water. It is called 880 ammonia. It has a relative density of 0.880. It is stored in tightly stoppered bottles in a cold place.