Sodium nitrate (NaNO3) is a compound commonly used in the food industry as a preservative. It is also used in fertilizers and explosives due to its oxidizing properties.
| IUPAC Name | Sodium Nitrate |
| Molecular Formula | NaNO3 |
| CAS Number | 7631-99-4 |
| Synonyms | Chile saltpeter, Cubic niter, Sodium saltpeter |
| InChI | InChI=1S/NO3.Na/c2-1(3)4;/q-1;+1 |
Sodium Nitrate Properties
Sodium Nitrate Formula
The chemical formula of sodium nitrate is NaNO3. The formula represents the number and types of atoms that make up a molecule of sodium nitrate. It indicates that each molecule of sodium nitrate contains one sodium atom, one nitrogen atom, and three oxygen atoms. The formula is important for understanding the chemical properties of sodium nitrate and for its use in various applications.
Sodium Nitrate Molar Mass
NaNO3 has a molar mass of 84.9947 g/mol. The molar mass is the mass of one mole of a substance and is calculated by adding the atomic masses of all the atoms in a molecule. NaNO3 contains one Na atom, one N atom, and three O atoms. The atomic masses of these atoms are 22.98977 g/mol for sodium, 14.00674 g/mol for nitrogen, and 15.9994 g/mol for oxygen. Therefore, the molar mass of NaNO3 is calculated as follows:
Molar mass = (1 x 22.98977) + (1 x 14.00674) + (3 x 15.9994) = 84.9947 g/mol
Sodium Nitrate Boiling Point
The boiling point of NaNO3 is 380 °C (716 °F). Boiling point is the temperature at which a substance changes from a liquid to a gas at atmospheric pressure. NaNO3 is an ionic compound with strong intermolecular forces that hold its particles together. These intermolecular forces require a high amount of energy to be broken, which is why the boiling point of NaNO3 is relatively high.
Sodium Nitrate Melting Point
NaNO3 has a melting point of 308 °C (586 °F). Melting point is the temperature at which a substance changes from a solid to a liquid at atmospheric pressure. NaNO3 is an ionic compound that has a crystalline structure with strong ionic bonds between its particles. These bonds require a high amount of energy to be broken, which is why the melting point of NaNO3 is relatively high.
Sodium Nitrate Density g/mL
The density of NaNO3 is 2.257 g/mL. Density is the mass per unit volume of a substance. NaNO3 is a white, crystalline solid with a relatively high density due to its tightly packed particles. It is important to note that the density of NaNO3 may vary depending on factors such as temperature and pressure.
Sodium Nitrate Molecular Weight
The molecular weight of NaNO3 is 84.9947 g/mol. Molecular weight is the sum of the atomic weights of all the atoms in a molecule. As mentioned earlier, NaNO3 contains one sodium atom, one nitrogen atom, and three oxygen atoms, which contribute to its molecular weight.
Sodium Nitrate Structure
NaNO3 has a crystalline structure composed of Na+ and NO3- ions. The Na+ cations and NO3- anions are arranged in a lattice structure held together by strong ionic bonds. The structure of NaNO3 is important for understanding its physical and chemical properties.
| Appearance | White crystals or powder |
| Specific Gravity | 2.257 g/cm3 at 20°C |
| Color | Colorless |
| Odor | Odorless |
| Molar Mass | 84.9947 g/mol |
| Density | 2.257 g/cm3 at 20°C |
| Melting Point | 308 °C (586 °F) |
| Boiling Point | 380 °C (716 °F) |
| Flash Point | Not applicable |
| Water Solubility | 87 g/100 mL (20 °C) |
| Solubility | Soluble in glycerol, ammonia, and hydrogen peroxide. Insoluble in alcohol. |
| Vapour Pressure | 0.003 mm Hg at 20 °C |
| Vapour Density | Not applicable |
| pKa | -1.4 |
| pH | 7 (10% solution in water) |
Sodium Nitrate Safety and Hazards
NaNO3 may pose several hazards to human health and the environment. It is a mild irritant and can cause skin and eye irritation upon contact. Inhalation of NaNO3 dust may also cause respiratory irritation. NaNO3 can react with combustible materials and may cause a fire or explosion. It is also toxic to aquatic life and should not be released into waterways. NaNO3 should be handled with care and proper protective equipment should be worn when handling it. It should be stored in a dry, well-ventilated area away from incompatible materials. Proper disposal methods should also be followed to prevent environmental contamination.
| Hazard Symbols | O, Xi |
| Safety Description | Avoid contact with combustible materials, wear protective equipment, and store in a dry, well-ventilated area. Dispose of properly. |
| UN IDs | UN1498 (anhydrous) / UN1499 (fused) |
| HS Code | 28342910 |
| Hazard Class | 5.1 (Oxidizing agent) |
| Packing Group | III |
| Toxicity | LD50 (oral, rat): 1260 mg/kg |
Sodium Nitrate Synthesis Methods
Several methods can synthesize NaNO3, including reacting nitric acid with sodium hydroxide or reacting nitric acid with sodium carbonate.
The first method involves gradually adding a solution of sodium hydroxide to a solution of nitric acid while stirring until the pH reaches 7-8. The solution reacts to form NaNO3, which a person can evaporate and crystallize to obtain the solid compound.
Another method involves the reaction of sodium carbonate with nitric acid. The person adds sodium carbonate to nitric acid until effervescence ceases and then heats the mixture until the evolution of carbon dioxide stops. They then evaporate and crystallize the resulting solution to obtain NaNO3.
The production of NaNO3 can result in obtaining it as a by-product through the production of nitric acid or by oxidizing ammonia with a platinum catalyst.
Sodium Nitrate Uses
NaNO3 has a wide range of industrial, agricultural, and medical applications due to its chemical and physical properties. Some of the uses of NaNO3 include:
- Fertilizer: Commonly used as a nitrogen fertilizer in agriculture due to its high solubility and fast-release properties.
- Food Preservative: Used as a food preservative to prevent the growth of bacteria and fungi in processed meats such as ham, bacon, and hot dogs.
- Glass Production: Used as a flux in the production of glass to lower its melting point and improve its clarity.
- Pyrotechnics: A key ingredient in the production of fireworks and other pyrotechnic devices due to its oxidizing properties.
- Heat Transfer Fluid: Used as a heat transfer fluid in solar power plants to store and transfer thermal energy.
- Medical Applications: Used in the treatment of angina pectoris, a heart condition that causes chest pain due to insufficient blood flow to the heart.
- Industrial Applications: Also used in the production of dyes, bleaches, and other chemicals.
Questions:
Q: Is sodium nitrate soluble in water?
A: Yes, NaNO3 is highly soluble in water, with a solubility of 91 grams per 100 milliliters of water at room temperature.
Q: What is sodium nitrate used for?
A: NaNO3 is used for a variety of purposes, including as a fertilizer, food preservative, glass production flux, pyrotechnic oxidizer, heat transfer fluid, and in medical and industrial applications.
Q: Is sodium nitrate a strong electrolyte?
A: Yes, NaNO3 is a strong electrolyte, meaning that it completely dissociates into ions when dissolved in water, allowing for the conduction of electricity.
Q: Is NaNO3 soluble in water?
A: Yes, NaNO3 is highly soluble in water, with a solubility of 91 grams per 100 milliliters of water at room temperature.
Q: Is NaNO3 soluble?
A: Yes, NaNO3 is soluble in water, but it is insoluble in some organic solvents such as ethanol and ether.
Q: Which salt is produced when NH4OH reacts with HNO3? KNO2, NaNO3, NH4NO3, or NH4NO2?
A: The salt produced when NH4OH reacts with HNO3 is NH4NO3, also known as ammonium nitrate.
Q: Is NaNO3 an acid or base?
A: NaNO3 is a neutral compound and neither an acid nor a base.
Q: What is NaNO3?
A: NaNO3 is the chemical formula for sodium nitrate, which is a white crystalline solid with a variety of industrial, agricultural, and medical applications.