Orthophosphoric acid

Community Right-To-Know List. Reported in EPA TSCA Inventory. EPA Genetic Toxicology Program.

OSHA PEL: TWA 1 mg/m³; STEL 3 mg/m³
ACGIH TLV: TWA 1 mg/m³; STEL 3 mg/m³
DOT Classification:  8; Label: Corrosive

For occupational chemical analysis use OSHA: #ID-111 or NIOSH: Acids, Inorganic, 7903.

Phosphoric acid is clear colorless liquid, used in the manufacture of fertilizers and soap. With the cas number 7664-38-2, it is also called orthophosphoric acid. The product categories of phosphoric acid is INORGANIC & ORGANIC CHEMICALS; Inorganics; HPLC Buffer ;HPLC Buffers - SolutionChromatography/CE Reagents; Solution; PAlphabetic; Analytical Standards; MRStable Isotopes; PER - POLA; Spectroscopy; Alphabetical Listings; Flavors and Fragrances; Organic Phosphonates. Phosphoric acid (also known as orthophosphoric acid or phosphoric(V) acid) is a mineral (inorganic) acid having the chemical formula H3PO4. Orthophosphoric acid molecules can combine with themselves to form a variety of compounds which are also referred to as phosphoric acids, but in a more general way.

Properties of Phosphoric acid as follows:
 (1)ACD/LogP: -1.644; (2)ACD/LogD (pH 5.5): -4.91; (3)ACD/LogD (pH 7.4): -5.88; (4)ACD/BCF (pH 5.5): 1.00; (5)ACD/BCF (pH 7.4): 1.00; (6)#H bond acceptors: 4; (7)#H bond donors: 3; (8)Index of Refraction: 1.51; (9)Molar Refractivity: 13.527 cm³; (10)Molar Volume: 45.2 cm³; (11)Polarizability: 5.363 10-24cm³; (12)Surface Tension:136.343002319336; (13)dyne/cm Density: 2.168 g/cm³; (14)Boiling Point: 157.999 °C at 760 mmHg; (15)Vapour Pressure: 1.40699994564056 mmHg at 25°C.

Preparation of Phosphoric acid:
Phosphoric acid includes three routes - the Thermal Process, the Wet Process and the dry Kiln Process.
Firstly let us introduce thermal phosphoric acid.This very pure phosphoric acid is obtained by burning elemental phosphorus to produce phosphorus pentoxide and dissolving the product in dilute phosphoric acid. Because most impurities present in the rock have been removed when extracting phosphorus from the rock in a furnace, this produces a very pure phosphoric acid. The end result is food-grade, thermal phosphoric acid; however, for critical applications, additional processing to remove arsenic compounds may be needed.
Secondly let us introduce wet phosphoric acid
See also: Nitrophosphate process
Wet process phosphoric acid process: add sulfuric acid to tricalcium phosphate rock, typically found in nature as apatite.
The reaction is: Ca5(PO4)3X + 5 H2SO4 + 2 H2O → 3 H3PO4 + 5 CaSO4 · 2 H2O + HX
where X may include OH, F, Cl, and Br
The initial phosphoric acid solution may contain 23-33% P2O5, but can be concentrated by the evaporation of water to produce commercial- or merchant-grade phosphoric acid, which contains about 54% P2O5. Further evaporation of water yields superphosphoric acid with a P2O5 concentration above 70%.

Uses of Phosphoric acid: 
Phosphoric acid is used as an additive to acidify foods and beverages like various colas. This use has managed to stir up a controversy regarding the health effects that this may have on the human body. It provides a tangy or a sour taste and being a mass produced chemical, it is available in large quantities easily. Another most important use is in medicine and dentistry. Phosphoric acid is used as an ingredient in over-the-counter anti-nausea medications which also happen to contain high levels of sugar, that is, glucose and fructose. In dentistry, this acid is combined with zinc powder to form zinc phosphate, which is used as a temporary dental cement.This is an important acid that is prepared by different routes. Its application in various industries ranging from metallurgy to the food industry make this a popular acid.

When you are using Phosphoric acid, please be cautious about it as the following: 
(1)Keep container tightly closed; 
(2)Keep away from sources of ignition - No smoking;
(3)In case of contact with eyes, rinse immediately with plenty of water and seek medical advice;
(4)Wear suitable protective clothing;
(5) Wear suitable gloves;

You can still convert the following datas into molecular structure:
(1)SMILES:OP(=O)(O)O;
(2)Std. InChI:InChI=1S/H3O4P/c1-5(2,3)4/h(H3,1,2,3,4);
(3)Std. InChIKey:NBIIXXVUZAFLBC-UHFFFAOYSA-N;

The toxicity data of Phosphoric acid is as follows: