The key difference between sodium nitrate and sodium nitrite is that sodium nitrate appears as colourless crystals whereas sodium nitrite appears as yellowish crystals.
Both sodium nitrate and sodium nitrite are ionic compounds of sodium, nitrogen and oxygen chemical elements. These two compounds differ from each other according to the anion present along with the sodium cation.
CONTENTS
1. Overview and Key Difference
2. What is Sodium Nitrate
3. What is Sodium Nitrite
4. Side by Side Comparison – Sodium Nitrate vs Sodium Nitrite in Tabular Form
5. Summary
What is Sodium Nitrate?
Sodium nitrate is an inorganic compound which has the chemical formula NaNO3. It appears as a white-colourless crystalline solid. It is an alkali metal nitrate salt, which is named as Chile saltpetre in mineralogy. This compound is highly water-soluble. Upon dissolution, it forms sodium cations and nitrate anions. Therefore, it is useful as a readily nitrate available source in different synthesis processes, fertilizer production, etc.
Figure 01: Sodium Nitrate
The molar mass of sodium nitrate is 84.9 g/mol. It has a sweet odor. In addition to mining from deposits, we can synthesis sodium nitrate in the laboratory as well. There, we can neutralize nitric acid with sodium carbonate or sodium bicarbonate. It is also possible to do this neutralization using sodium hydroxide. The crystal structure of this produced sodium nitrate can be defined as a trigonal crystal structure, but sometimes it gives rhombohedral crystal structure.
What is Sodium Nitrite?
Sodium nitrite is an inorganic compound having the chemical formula NaNO2. It has a white-yellowish crystalline appearance. This compound is highly water-soluble and hygroscopic as well. The molar mass of this compound 68.9 g/mol. Moreover, the crystal structure of sodium nitrite is orthorhombic. The industrial production of sodium nitrite can be done two ways: reduction of nitrate salts or oxidation of lower nitrogen oxides.
Figure 02: Sodium Nitrite
The major use of sodium nitrite in the industry is to produce organonitrogen compounds. There, we can use it as a reagent for the conversion of amines into diazo compounds. These diazo compounds are the key to many azo compounds such as dyes. Moreover, sodium nitrite is an efficient drug in cyanide poisoning. It is also an important food additive because the addition of sodium nitrite is an easy way to give the processed meat a shady pink colour. The taste of the meat is also enhanced by this compound. However, sodium nitrite has been recognized as a slightly toxic compound.
What is the Difference Between Sodium Nitrate and Sodium Nitrite?
Both sodium nitrate and sodium nitrite are ionic compounds of sodium, nitrogen and oxygen chemical elements. The key difference between sodium nitrate and sodium nitrite is that sodium nitrate appears as colourless crystals whereas sodium nitrite appears as yellowish crystals. The anion in sodium nitrate is NO3– and in sodium nitrite it is NO2–. Both these compounds are water-soluble but sodium nitrite is hygroscopic as well.
Moreover, the crystal structure of sodium nitrate is trigonal while the crystal structure of sodium nitrite is orthorhombic. We can produce sodium nitrate via neutralizing nitric acid with sodium carbonate or sodium bicarbonate. We can produce sodium nitrite in one of the two ways: reduction of nitrate salts or oxidation of lower nitrogen oxides.
Below infographic summarizes the difference between sodium nitrate and sodium nitrite.
Summary – Sodium Nitrate vs Sodium Nitrite
Both sodium nitrate and sodium nitrite are ionic compounds of sodium, nitrogen and oxygen chemical elements. The key difference between sodium nitrate and sodium nitrite is that sodium nitrate appears as colourless crystals whereas sodium nitrite appears as yellowish crystals.
Reference:
1. Helmenstine, Anne Marie. “How To Grow Sodium Nitrate Crystals.” ThoughtCo, Mar. 26, 2019, Available here.
Image Courtesy:
1. “Dusičnan sodný” By Ondřej Mangl – Own work (Public Domain) via Commons Wikimedia
2. “Sodium nitrite crystals” By W. Oelen – (CC BY-SA 3.0) via Commons Wikimedia