Nessler's Reagent Chemical Properties

Melting point:

120-127 °C(lit.)

Boiling point:

105°C

Density 

1.16 g/mL at 20 °C

Flash point:

>230 °F

solubility 

very soluble in H2O; soluble in ethanol,ethyl ether, acetone

form 

Liquid

Specific Gravity

1.097

color 

Yellow to orange

Odor

Odorless

Water Solubility 

Soluble in water.

Sensitive 

Hygroscopic

Merck 

13,7773

Exposure limits

ACGIH: TWA 0.025 mg/m3 (Skin)
NIOSH: IDLH 10 mg/m3; TWA 0.05 mg/m3; Ceiling 0.1 mg/m3

Stability:

Stable, but light sensitive. Incompatible with strong oxidizing agents.

InChIKey

OPCMAZHMYZRPID-UHFFFAOYSA-J

EPA Substance Registry System

Potassium mercuric iodide (7783-33-7)

Safety Information

Hazard Codes 

T,N,T+

Risk Statements 

26/27/28-33-35-51/53-52/53-23/24/25-48/21/22-25-50/53-68-24/25

Safety Statements 

45-36/37-61-36/37/39-28-26-60-13

RIDADR 

UN 3287 6.1/PG 3

WGK Germany 

3

RTECS 

OU9670000

F 

8-30

TSCA 

Yes

HazardClass 

6.1

PackingGroup 

II

HS Code 

28521000

Hazardous Substances Data

7783-33-7(Hazardous Substances Data)

MSDS

• Language:English Provider:SigmaAldrich
• Language:English Provider:ALFA

Nessler's Reagent Usage And Synthesis

Chemical Properties

light yellow liquid

Uses

Mercury(II) potassium iodide is used as a pharmaceutical intermediate. It is also used as reagents, chemical research and organic intermediates.

Uses

Nessler's reagent (K2[HgI4]) is used to detect the presence of ammonia, particularly in very small amounts.

Definition

Nessler's Reagent is a periodometallate salt that is solution of mercuric iodide in potassium iodide. It contains a tetraiodomercurate(2-).

Preparation

It is prepared by mixing 2g potassium iodide in 5ml water. To this solution, 3g of mercury (II) iodide is added, and the resulting solution is made to 20ml. Finally, 40g potassium hydroxide (30 %) is added to provide the alkaline base.

General Description

Mercuric potassium iodide, [solid] appears as odorless yellow crystals. Crystallizes with either one, two or three molecules of water. Soluble in water and denser than water. Commercially available in the anhydrous form. Highly toxic by ingestion, inhalation, and skin absorption.

Air & Water Reactions

Deliquescent. Very water soluble.

Reactivity Profile

MERCURIC POTASSIUM IODIDE is incompatible with acetylene, ammonia, chlorine dioxide, azides, calcium (amalgam formation), sodium carbide, lithium, rubidium, copper . NESSLER'S REAGENT behave in aqueous solution as a weak acid.

Hazard

Highly toxic by ingestion, inhalation, and skin absorption.

Health Hazard

Highly toxic, may be fatal if inhaled, swallowed or absorbed through skin. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.

Fire Hazard

Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Containers may explode when heated. Runoff may pollute waterways.

Safety Profile

A poison. Moderately toxic by skin contact and intraperitoneal routes. When heated to decomposition it emits very toxic fumes of Hg, K2O, and I-. See also MERCURY.

Nessler's Reagent(7783-33-7)Related Product Information

• Lead(II) iodide
• Aluminon
• COBALT THIOCYANATE
• Bismuth nitrate oxide
• Ammonium phosphate dibasic
• Potassium dichromate
• Lucas
• Zinc hydroxide
• MERCURY(II) SULFATE
• Nessler
• NESSLER'S REAGENT
• Potassium iodide
• SAMARIUM(II) IODIDE
• BISMUTH POTASSIUM IODIDE
• Sodium iodide
• Cesium iodide
• Propidium iodide
• NESSLER'S REAGENT