Final answer:
Sodium nitrite has the chemical formula NaNO2 and is used to preserve the color and limit bacterial growth in meats. It is composed of sodium ions and nitrite ions, and while helpful for preservation, its use is regulated due to the potential formation of carcinogenic nitrosamines during cooking.
Step-by-step explanation:
The chemical formula of sodium nitrite, which is used as an antimicrobial salt in the production of bacon and salami, is NaNO2. Sodium nitrite is an ionic compound consisting of sodium ions (Na+) and nitrite ions (NO2−). The role of sodium nitrite in food preservation is twofold: it helps to limit the growth of bacteria that can cause food poisoning and preserves the red color of meat which consumers find appealing. However, the use of sodium nitrite is regulated due to the potential health risks associated with nitrosamines, which can form when nitrite-preserved meats are exposed to high temperatures during cooking and are known to be carcinogenic.
To draw the resonance forms of the nitrite ion (NO2−), you would depict the nitrogen atom with a single-bonded and a double-bonded oxygen atom, with the charges appropriately distributed between the oxygen atoms in different drawings. Unfortunately, this response format does not allow for the graphical representation of the resonance structures, but they illustrate the concept that the double bond can be located on either oxygen, with the other oxygen atom carrying a negative charge.