Sodium Nitrate

An Overview of Sodium Nitrate – NaNO3

As you know, chemistry can be the most scoring subject in examinations if studied with little extra effort. So, here are some important notes on sodium nitrate for your convenient.

It is a chemical compound of nitrate, commonly called Chile saltpeter. The chemical formula of this compound is NaNO3. Its mineral form is again called soda niter or nitratite, nitratine. NaNO3 name is frequently used in industrial production of fertiliser, smoke bomb, pottery enamels, glass, food preservatives, pyrotechnics, etc. 


What is Sodium Nitrate?

Sodium nitrate is the chemical name for NaNO3. It is an inorganic alkali metal nitrate salt. This compound is made of one sodium cation or Na+ and one nitrate anion or NO3-. Also, NaNO3 compound name, a white coloured crystalline solid, sodium nitrate in water is extremely soluble.  

Though it is non-flammable, this powerful oxidising agent can violently react with several flammable compounds. Usually, NaNO3 on heating above 538oC can decompose explosively. 


Structure of Sodium Nitrate

To understand the answer to what is NaNO3 and how it reacts with other compounds, you need to evaluate the structure of NaNO3. Its composition defines an ionic bond of one NO3- and one Na+. You can see the sodium nitrate structure in the diagram below.

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Moreover, you can opt for the NaNO3 Lewis structure to obtain a better understanding of the molecular arrangement. The simplified depiction of the electron structure in the outermost shell or valence shell of a molecule is termed as Lewis structure. 

By this structure, you can identify the arrangement of electrons around separate atoms inside a molecule. In this structure, electrons are represented as dots. However, for bonding electrons, a line can be used between two atoms as well. 

Here is the Lewis structure of NaNO3-

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While studying chemistry, you should not only learn the chemical formula of sodium nitrate NaNO3 but also understand its structure. Once you know the molecular bonding and structure, you can easily memorise what is the chemical formula for sodium nitrate.

Moreover, understanding the molecular or Lewis structure is also vital to comprehend all its chemical reactions. For example, if the concept of NaNO3 structure is clear, you can be confident about the answers of how the molecules will bond in different chemical reactions.


Preparation of Sodium Nitrate 

From the above information, you can understand what is the name of NaNO3 or what is the formula for sodium nitrate. These are the most basic information about this chapter that you should know. However, now the discussion will be on sodium nitrate preparation.

Here are the chemical equations of nitric acid neutralisation by industrial synthesising. The reactions happen between sodium nitrate and sodium hydroxide, sodium carbonate, and sodium bicarbonate. 

  • NaOH + HNO3 🡪 NaNO3 + H2O

Nonetheless, this rection with sodium hydroxide is extremely exothermic as HNO3 is powerful acid and NaOH is a powerful base.

  • 2 HNO3 + Na2NO3 🡪 2 NaNO3 + H2O +CO2

  • HNO3 + NaHCO3 🡪 NaNO3 + H2O +CO2

However, sodium nitrate can be produced by replacing nitric acid with ammonium nitrate in these reactions.

NaHCO3 + NH4NO3 🡪 NH4HCO3 + NaNO3

Na2CO3 + 2 NH4NO3 🡪 (NH4)2CO3 + 2 NaNO3

NaOH + NH4NO3 🡪 NH4OH + NaNO3


Properties of Sodium Nitrate

For your upcoming examinations, you need to know more than just about NaNO3 chemical name and its preparation. It is important to identify some properties of NaNO3 for future reference.

  • Chemical Information

Chemical name of NaNO3 

Sodium nitrate

NaNO3- name of compounds

One Na+ and one NO3-

Molar mass

84.99 grams/mole

Density

2.257 grams/centimeter3

NaNO3 melting point

308oC or 581 K

Boiling point of NaNO3 

380oC or 653 K

  • Physical Properties

Here is some information about the physical properties of sodium nitrate.

  1. NaNO3 is solid that appears in a crystalline structure and white colour, in room temperature.

  2. Its crystal structure can be categorised into two types – trigonal and rhombohedral.

  3. This compound comes with a sweet odour.

  4. It has a slightly bitter and saline type of taste.

  5. At 25oC temperature, the water solubility of NaNo3 corresponds to 91.2 gram per 100 millilitres.

  6. Sodium nitrate is also a highly ammonia soluble compound.

  7. NaNO3 is also slightly soluble in methanol and ethanol.

  • Chemical Properties

Some Chemical Properties Of NaNO3 Are

  1. After dissolving in water, NaNO3 breaks into One Na+ and one NO3-.

  2. This is a highly powerful oxidising agent. Thus, with reducing agents, NaNO3 reacts violently.

  3. It decomposes at high temperature and produces oxygen and nitrogen oxides. Due to this oxygen production, it can increase the fire hazard and lead to explosive decomposition.

  4. During decomposition, NaNO3 emits toxic gasses like sodium oxide and nitrogen oxide.

  5. The pH balance of NaNO3 aqueous solution is neutral.


Other Names of NaNO3

Beside sodium nitrate, there are several names for NaNO3. As a medical aspirant, you should know some of its synonyms as well. As said earlier, Chile saltpeter is the most popular name of this compound. Here are some other names-

  • Nitrate of soda

  • Cubic niter

  • Nitratine

  • Soda niter

  • Sodium saltpeter

  • Nitric acid monosodium salt


Did You Know

  1. The compound names of NaNO3 are Na+ or sodium cation and NO3- or nitrate anion.

  2. The chemical name of NaNO3 is sodium nitrate. 

  3. Chile saltpeter is nothing but sodium nitrate or NaNO3


Sodium Nitrate in Food

NaNO3 has been treated as preservatives in meat curing for years. Though this chemical compound does not have any antioxidant activity, it can be functional if reduced to nitrite. Sodium nitrate can majorly help in stabilising meat colour, improving texture, developing the characteristics flavour of cured meat, and diminishing antimicrobial activities. 

It can also act as metal chelators that help the formation of nitroso compounds. These chemical compounds carry antioxidant properties and form stable nitric oxides from heme proteins.

Thus, foods that contain sodium nitrate are various processed meats like ham, bacon, salami, pate, hot dog, dried fish, sausages, smoked salmon, etc. In examinations, if you get a question like what foods have sodium nitrite, hopefully, you can answer that after reading this content.


Effect of Sodium Nitrate on Plant Growth

Nitrogen is one of the most vital elements that should be present in the soil for plant growth. Thus, the application of nitrogen fertiliser can rapidly help in crop growth. During the initial stage, a visible influence of sodium nitrate on plant growth can be observed. It can act as a stimulator. However, often use of fertiliser can lead the plant to wilt. Moreover, plants can also stop growing, or the process will become slow.

So, this erroneous practice must be discredited.


Application Process of Sodium Nitrate

As sodium nitrate is completely water-soluble, and also as the soil colloids cannot absorb the nitrate ion, you may wonder how sodium nitrate should be applied. For maximum result, it must be used for initial utilisation. The major problem is the drainage of nitrate with water when it is applied to sands that have open subsoils. In these types of application, the most amount of nitrite is used easily.

Even if it is applied to clay, the quantity should not be more than what plants can utilise within a generous period of time. This way, nitrogen leaching can be minimised as well as plant root injuries due to excessive salt presence can be avoided. 


Uses of Sodium Nitrate

Due to the high water solubility and nitrogen presence, and low cost, there are several uses of sodium nitrate as fertilisers. However, there are some other uses of this compound listed below-

  • By utilising NaNO3, hybrid aqua regia can be formed. These hybrids are useful to dissolve gold.

  • For centuries, sodium nitrate is used as food preservatives.

  • In different fireworks, it can act as an oxidiser.

  • This is also regarded as one of the most effective instant cold packs.

  • Sodium nitrate works as heat storage and transferrer in solar plants.

  • It can also act as a substitute for potassium nitrate in gunpowder.

Thus, these are the most common uses of NaNo3 as it is one of the most cost-effective and huge sources of nitrogen. Moreover, in various rocket propellants, this compound is majorly utilised as well.


History

During the 19th century, NaNo3 was known as ‘white gold’. Chile, a South American country, fought against Peru and Bolivia to retain their territory in the desert of the Atacama, known for its rich deposits of sodium nitrate.

However, the popularity of the Haber process gradually reduced the demand for natural NaNo3. Due to the increase of synthetic NaNo3 production, the mining of natural deposits has also become obsolete.

For more extensive information about sodium nitrate, and other topics of chemistry, you can visit our Vedantu website now. You can also download our Vedantu app for a better learning experience.

FAQ (Frequently Asked Questions)

1. What is the Name of NaNo3?

Sodium nitrate is the name of NaNo3.

2. Why is NaNo3 Bad?

For plants, overuse of this compound can injure the root. Also, for animals, excessive use of NaNo3 can narrow down or harden the arteries and lead to heart diseases.

3. What Is Sodium Nitrate Used For?

NaNo3 is mostly used as fertiliser and food preservatives.

4. What Is White Gold?

NaNo3 or sodium nitrate is known as white gold.