General Description
AMMONIUM THIOSULFATE(7783-18-8) is a white crystalline solid. AMMONIUM THIOSULFATE(7783-18-8) is very soluble in water. The primary hazard is the threat posed to the environment. Immediate steps should be taken to limit its spread to the environment. AMMONIUM THIOSULFATE(7783-18-8) is used in photography, in chemical analysis, and for many other uses.
Reactivity Profile
AMMONIUM THIOSULFATE is sensitive to heat. This chemical is incompatible with magnesium and aluminum powder. Mixtures with sodium chlorate can cause an exothermic reaction which can then decompose explosively. . Reacts with strong oxidizers such as chlorates, nitrates, and nitrites to release toxic ammonia, hydrogen sulfide, and sulfur trioxide gases. Will not polymerize. Ammonia, hydrogen sulfide, and oxides of nitrogen and oxides of sulfur may form in fires [USCG, 1999].
Air & Water Reactions
Hygroscopic. Very soluble in water.
Health Hazard
Inhalation of dust may irritate respiratory system. Ingestion could be harmful. Contact with eyes or skin may cause irritation.
Potential Exposure
Used as an agricultural chemical and
fungicide, metal lubricant; in cleaning metals; in photographic
chemicals, making other chemicals. A laboratory
reagent.
Fire Hazard
Special Hazards of Combustion Products: Toxic ammonia, hydrogen sulfide, and oxides of nitrogen and sulfur may form in fires.
First aid
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least
15 minutes, occasionally lifting upper and lower lids. Seek
medical attention immediately. If this chemical contacts the
skin, remove contaminated clothing and wash immediately
with soap and water. Seek medical attention immediately.
If this chemical has been inhaled, remove from exposure,
begin rescue breathing (using universal precautions, including
resuscitation mask) if breathing has stopped and CPR if
heart action has stopped. Transfer promptly to a medical
facility. When this chemical has been swallowed, get medical
attention. Give large quantities of water and induce
vomiting. Do not make an unconscious person vomit.
Shipping
UN3077 Environmentally hazardous substances,
solid, n.o.s., Hazard class: 9; Labels: 9-Miscellaneous hazardous
material, Technical Name Required.
Incompatibilities
Contact with sodium chlorate may cause
a violent reaction. Corrodes brass, copper, and copperbased
metals.
Chemical Properties
Ammonium thiosulfate is a white crystalline
solid with an ammonia odor.
Chemical Properties
white or colourless crystals
Waste Disposal
Incinerate. It may be possible
to dispose of waste material at a municipal facility if
treated, neutralized and oxidized.
Physical properties
Colorless, monoclinic crystal; hygroscopic; decomposes on heating above 100°C; density 1.679 g/cm3; very soluble in water (64 g/100 g at 20°C), insoluble in alcohol, and slightly soluble in acetone.
Uses
To clean "white" metal; in photography; in lubricants for metal cold-working.
Agricultural Uses
Ammonium thiosulphate, [(NH4)2S2O3 or ATS] is a
crystalline salt, the aqueous solution of which is
commonly used as a liquid fertilizer. Crystalline
ammonium thiosulphate contains 19% nitrogen and 43 %
sulphur and its aqueous solution contains 12% nitrogen
and 26 % sulphur.
Ammonium thiosulphate is compatible with nitrogen
and nitrogen-potassium solutions, which are neutral or
slightly acidic (pH 5.8). It is also used as a suspension:
As it is non-corrosive, it can be stored in steel or
aluminumdrums.
Ammonium thiosulphate is prepared by the reaction
of sulphur dioxide and aqueous ammonia, followed by a
further reaction with elemental sulphur.
ATS can be applied directly to soils or as a foliar spray
through sprinkler irrigation systems. When applied to soils,
ATS decomposes into ammonium sulphate and colloidal
sulphur. The ammonium sulphate is available immediately
to plants, while the sulphur gets oxidized over a period of
time to sulphate ion (SO42-) It is thus available to plants for
a longer time.
Ammonium thiosulphate also acts as a urease
inhibitor. When added to a urea-ammonium nitrate
solution, it inhibits urease activity for a month or so. In
industry, it is also used as a photographic fixing agent,
analytical reagent, fungicide and as a brightener in silverplating
baths.
Safety Profile
Moderately toxic by ingestion.When heated to decomposition it emits toxic vapors ofNH4- and SOx.
storage
Color Code—Green: General storage may beused. Prior to working with this chemical you should betrained on its proper handling and storage. Store in tightlyclosed containers in a cool, well-ventilated area away fromoxidizers, acids, water, or combustible materials.
