Silver Nitrate

What is Silver Nitrate?

Silver nitrate is a chemical compound with the formula AgNO3. It consists of an ionic bond between the silver cation (Ag+) and the nitrate anion (NO3). Due to the ionic nature of this compound, it readily dissolves in water and dissociates into its constituent ions.

Silver nitrate is a precursor to many compounds of silver, including the silver compounds used in photography. When compared to silver halides, which are used in photography due to their sensitivity to light, AgNO3 is quite stable when exposed to light.

Structure of AgNO3

An illustration describing the structure of the silver nitrate molecule is provided below. It can be observed that silver has an oxidation number of 1 in this compound.

Silver Nitrate

The nitrate ion described above consists of one nitrogen atom which is surrounded by three oxygen atoms. The nitrogen-oxygen bonds in this ion are similar to each other. The formal charge assigned to the nitrogen atom is -1, whereas each oxygen atom holds a charge of -⅔. The net charge associated by the nitrate ion is -1, which is quenched by the +1 charge held by the Ag+ ion via an ionic bond in AgNO3. It can be noted that the structure of the nitrate ion is stabilized by resonance.

Properties of Silver Nitrate

Some important physical and chemical properties of silver nitrate are listed in this subsection.

Physical Properties

  • The molar mass of silver nitrate is 169.872 grams per mole.
  • AgNO3 as a colorless appearance in its solid state and is odorless.
  • In its solid state, it has a density of 4.35 grams per cubic centimeter. Its density in the liquid state at a temperature of 210oC corresponds to 3.97 g/cm3.
  • The melting and boiling points of silver nitrate are 482.8 K and 713 K respectively. However, this compound tends to decompose at temperatures approaching its boiling point.
  • Silver nitrate, like most ionic compounds, dissolves readily in water. Its solubility in water corresponds to 122g/100mL at 0oC and 256g/100mL at a temperature of 25o
  • The crystal structure of AgNO3 is orthorhombic.

Chemical Properties

  • The hazards of AgNO3 include its toxic and corrosive nature.
  • The reaction between silver nitrate and ethanol is explosive.
  • The silver present in this compound is displaced by copper, which forms copper nitrate. The chemical equation for this reaction is given by 2AgNO3 + Cu → Cu(NO3)2 + 2Ag
  • When heated to 440oC, this compound completely decomposes to give oxygen, nitrogen dioxide, and silver.

It can be noted that even though metal nitrates generally decompose to yield metal oxides, the decomposition reaction of silver nitrate gives rise to elemental silver because silver oxide decomposes at an even lower temperature than AgNO3.

Uses of Silver Nitrate

Silver nitrate has a wide range of applications in many fields such as biology, chemical synthesis, and medicine. Some of these uses of AgNO3 are listed below.

  • Silver nitrate is a very versatile compound because the nitrate ion can be replaced by other ligands that can bind to the silver ion.
  • Due to the ability of this compound to form a precipitate of silver halides when treated with halide ions, it is used while making photographic films.
  • Many silver-based explosives can be prepared with a precipitation reaction of silver nitrate.
  • In the field of inorganic chemistry, halides are extracted with the help of this compound.
  • The branch of chemistry known as analytical chemistry uses this reaction to check for the presence of halide anions such as the iodide, bromide, or chloride ions.
  • Mixtures of alkenes can be separated with the help of this compound since the silver cation binds with alkenes in a reversible fashion.
  • When diluted with water to a concentration of 0.5%, silver nitrate can serve as an antiseptic in many medical setups.
  • A diluted solution of AgNO3 can be administered to the eyes of a baby which is born to a mother suffering from gonorrhea, which combats the gonococcal bacteria and protects the baby from the onset of blindness.
  • This compound is also known to be used for the treatment and the removal of unwanted warts in human beings.

Thus, the important physical and chemical properties of silver nitrate are briefly described along with its properties. To learn more about this compound and other silver compounds such as silver chloride, register with BYJU’S and download the mobile application on your smartphone.

Practise This Question

Water is often treated with chlorine to