Sodium nitrate reacts with silver nitrate

Hazard classes + category
Oxidising solids 2
Corrosive to metals
Skin corrosion / irritation 1B
Hazardous to the aquatic environment. acute / chronic 1
HP rates (See note)
H 272, 290, 314, 400, 410
P 221, 264.1, 273, 280.1-3,303 + 361 + 353, 305 + 351 + 338, 390

special instructions
Special notes for schools
When working with silver nitrate or its solutions, it is necessary to wear protective goggles and protective gloves. Hands and the workplace should be washed well after each work. Skin, clothing or work surfaces that have been wetted with silver nitrate solution must be thoroughly cleaned with water, otherwise black-violet silver coatings will form under the action of light, which are difficult to clean. In general, only freshly prepared silver nitrate solutions should be used for chloride detection. This is provided in a small, black painted PE dropper bottle with a volume of 50 ml. Leftovers must be disposed of correctly. The ammoniacal silver nitrate solution used for mirroring must not be stored under any circumstances, as this can cause explosive crystals to form. It is not advisable to use larger quantities, as there is a risk, for example, with mirroring experiments. Carrying out the Tollens test for the detection of carbon monoxide in schools is problematic. Soluble silver compounds have a very high environmental hazard potential (see lethal concentration). Leftovers must be carefully collected and properly disposed of.

GBU Chloride detection with silver nitrate and Tollens sample
Silver nitrate forms clear crystals that appear white in the crystalline powder. The bitter metallic tasting silver salt has a strong corrosive and bactericidal effect. It is very soluble in water. The solution is weakly acidic. Even traces in a body of water can kill the organisms in it.

Silver (I) nitrate is reduced to finely divided black silver by organic substances such as glycerine, but also by dust particles, especially in the light. Therefore it has to be kept in the dark. Moistened skin turns brown after a few hours when exposed to light. However, the silver formed on the surface of the skin breaks down again after a few days. In the past, the silver salt was used to etch warts. Because of the discoloration on the skin, it was called Hellstone.

Potassium iodide can be used to remove the stains immediately. If potassium chloride is added to a silver (I) nitrate solution, light-sensitive silver chloride that is no longer soluble in water will flocculate:

AgNO3 + KCl AgCl + KNO3

Many silver salts can be produced in this way: With sodium hydroxide you get silver (I) oxide Ag2O, with sodium carbonate silver (I) carbonate and with potassium chromate you can produce silver chromate. If you mix a silver (I) nitrate solution with ethanol, the silver fulminate or crack silver CNOAg present in the crackling peas can be crystallized out (> legal notice). This is even more sensitive to touch than the initial explosive mercury. When converting ammoniacal silver nitrate solution to silver nitride Ag3N is also an explosive substance. This "fancy silver" is chemically different from silver fulminate or silver azide. The silver azide AgN3 is represented by the reaction of sodium azide with silver nitrate. It detonates just by touching it.

It is very dangerous if ammoniacal silver nitrate solutions for mirroring are left standing or stored for long periods of time. Then the explosive silver nitride crystals crystallize out. Simply turning the cap or shaking it a little can trigger the explosion. The experiment instructions for mirroring must be followed exactly. Only a few drops of dilute ammonia solution are necessary. It is recommended to use only small, clean test tubes for reflections and not more than 3 milliliters of the solution per batch. The mirroring solution is always produced directly in the test tube to be mirrored. Since the silver nitrate is normally completely reduced in this test variant, the remaining solutions can be disposed of in the wastewater immediately after the test. If there are residues of silver nitrate, the silver can be reduced by adding glucose. It is important that all vessels involved are thoroughly rinsed. It is imperative to wear protective goggles.

Tollens reagent is a mixture of 10% silver nitrate solution and 10% sodium hydroxide solution, to which a little ammonia solution is added until the silver oxide precipitation that has just occurred disappears again. The Tollens sample is used to detect functional groups with a reducing effect. Aldehydes are oxidized to alkanoic acids with Tollen's reagent, whereby elemental silver is formed. When carbon monoxide is introduced into Tollen's reagent, carbon monoxide is oxidized to carbon dioxide. The Tollens sample can be used to detect small amounts of carbon monoxide. Carrying out the Tollens sample in schools is problematic because the solution must only be freshly prepared and the leftovers must be disposed of correctly. It is recommended to use an electronic carbon monoxide detection device instead, such as is available from electronics supplies.
Dissolving silver in concentrated nitric acid gives silver (I) nitrate, which forms nitric oxide:

3 Ag + 4 ENT3  3 AgNO3 + 2 H.2O + NO

The nitrogen monoxide (NO) changes into red-brown nitrogen dioxide NO when it comes into contact with the air2 above. This experiment may only be carried out in a well-ventilated fume cupboard, as the nitrogen oxides are very toxic.