Tollens Test ,MSDS

Procedure:

Add one drop or a few crystals of unknown to the freshly prepared Tollens reagent. Gentle heating can be employed if no reaction is immediately observed.
Tollens reagent: Into a test tube which has been cleaned with 10% sodium hydroxide, place 2 mL of a 5% silver nitrate solution, and add a drop of 10% sodium hydroxide. Add 2% ammonia solution, drop by drop, with constant shaking, until the precipitate of silver oxide just dissolves.

Positive Test

Formation of silver mirror or black precipitate is a positive test.

Complications

The test tube must be clean and free of oil if a silver mirror is to be observed.
Easily oxidized compounds give a positive test. For example: aromatic amine, some phenols, -alkoxy and -dialkylaminoketones.


Safety data for silver nitrate

________________________________________
General:

Synonyms: lunar caustic, silver (I) nitrate, silver (1+) nitrate, nitric acid silver salt
Molecular formula: AgNO3
CAS No: 7761-88-8
EC No: 231-853-9
EC Index No: 047-001-00-2

Physical data

Appearance: colourless crystals or white powder
Melting point: 212 C
Boiling point: ca. 444 C (decomposes)
Specific gravity: 4.33
Vapour pressure:
Flash point: n/a
Explosion limits: n/a
Autoignition temperature:

Stability

Stable. Substances to be avoided include nonmetals, organic substances, alkali hydroxides, acetylidene, acetylene, aldehydes, nitriles, ammonia, alcohols, ammonium compounds, combustible materials, hydrazine and its derivatives, carbides, magnesium in powder form, alcohols. Light-sensitive. Strong oxidizing agent.

Toxicology

Poisonous. Causes burns. Long-term exposure can cause permanent blue-grey staining of eyes, mouth, throat and skin, (argyria) and may cause eye damage. Short contact can lead to deposition of black silver stains on the skin. Very destructive of mucous membranes. Skin and eye irritant. Experimental equivocal tumorigenic agent.

Toxicity data

(The meaning of any abbreviations which appear in this section is given here.)
ORL-MUS LD50 50 mg kg-1
UNR-MAN LDLO 29 mg kg-1
ORL-RBT LDLO 800 mg kg-1
SCU-GPG LDLO 62 mg kg-1
IVN-RBT LDLO 9 mg kg-1
Risk phrases
(The meaning of any risk phrases which appear in this section is given here.)
R22 R34 R50 R53.

Environmental information

Harmful in the environment - may cause long-term damage.
Transport information
(The meaning of any UN hazard codes which appear in this section is given here.)
UN No 1493. Hazard class 5.1. Packing group II. EMS No 5.1-06.

Personal protection

Safety glasses, gloves.
Safety phrases
(The meaning of any safety phrases which appear in this section is given here.)
S26 S45.