Sodium fluoride (NaF) is a chemical compound used to prevent tooth decay. It strengthens tooth enamel by remineralizing it and inhibits the growth of harmful oral bacteria.
| IUPAC name | Sodium fluoride |
| Molecular formula | NaF |
| CAS number | 7681-49-4 |
| Synonyms | Sodium monofluoride, Sodium fluoride anhydrous, Monosodium fluoride, Natrium fluoride, |
| Solutia SFL, Fluka 01178, 3M ESPE 12104, Sodium fluoride puriss., Sodium fluoride extrapure | |
| InChI | InChI=1S/FH.Na/h1H;/q;+1/p-1 |
Sodium Fluoride Properties
Sodium Fluoride Formula
The chemical formula of sodium fluoride is NaF. This means that each molecule of NaF consists of one Na+ ion and one F- ion. The formula is important in chemistry as it provides information about the types and number of atoms or ions in a molecule of a substance.
Sodium Fluoride Molar Mass
The molar mass of NaF is 41.99 g/mol. It is the sum of the atomic masses of one sodium atom and one fluorine atom, which are 22.99 g/mol and 19.00 g/mol, respectively. The molar mass is an important property in chemistry as it allows for the calculation of the number of moles of a substance based on its mass, and vice versa.
Sodium Fluoride Boiling Point
The boiling point of NaF is 1,705°C (3,101°F). This is the temperature at which the liquid form of NaF changes to its gaseous form. NaF has a relatively high boiling point compared to other F-compounds due to its strong ionic bond between Na+ ions and F- ions.
Sodium Fluoride Melting Point
The melting point of NaF is 993°C (1,819°F). This is the temperature at which the solid form of NaF changes to its liquid form. NaF has a relatively high melting point due to its strong ionic bond between Na+ ions and F- ions.
Sodium Fluoride Density g/mL
The density of NaF is 2.79 g/mL. This means that one milliliter of NaF weighs 2.79 grams. Density is an important property of a substance as it can be used to determine the mass of a substance based on its volume, or the volume of a substance based on its mass.
Sodium Fluoride Molecular Weight
The molecular weight of NaF is 41.99 g/mol. This is the sum of the atomic weights of sodium and fluorine in a molecule of NaF. Molecular weight is important in chemistry as it allows for the calculation of various properties of a substance, such as its density and molarity.
Sodium Fluoride Structure
NaF has a crystalline structure in its solid form. It consists of Na+ ions and F- ions arranged in a cubic lattice structure. The Na+ ions occupy the corners of the cube, while the fluoride ions occupy the centers of the cube’s faces. This arrangement results in a strong ionic bond between Na+ ions and F- ions.
| Appearance | White crystalline solid |
| Specific Gravity | 2.79 g/cm³ |
| Color | Colorless |
| Odor | Odorless |
| Molar Mass | 41.99 g/mol |
| Density | 2.79 g/mL |
| Melting Point | 993°C (1,819°F) |
| Boiling Point | 1,705°C (3,101°F) |
| Flash Point | Not applicable |
| Water Solubility | 4.24 g/100 mL (20°C) |
| Solubility | Soluble in alcohol and ether |
| Vapour Pressure | 1 mm Hg (713°C) |
| Vapour Density | 2.9 (air = 1) |
| pKa | 7.2 |
| pH | 7.6-8.4 (0.1M aqueous solution) |
Sodium Fluoride Safety And Hazards
NaF has some safety and hazard concerns. It is toxic if ingested in large amounts, and can cause nausea, vomiting, diarrhea, and abdominal pain. Inhalation of NaF dust can cause respiratory irritation and lung damage. It can also cause eye irritation and skin irritation upon contact. NaF is also corrosive to some metals and can react violently with strong acids. Proper handling, storage, and disposal procedures should be followed when working with NaF to avoid these hazards. It is important to always wear appropriate personal protective equipment when handling NaF.
| Hazard Symbols | T, N |
| Safety Description | Avoid ingestion, inhalation, skin and eye contact. Wear appropriate PPE. Follow safe handling, storage and disposal procedures. |
| UN IDs | UN1690 (for solid) |
| HS Code | 2826.12.00 |
| Hazard Class | 6.1 (Toxic substances) |
| Packing Group | II |
| Toxicity | Toxic if ingested or inhaled in large amounts. Can cause respiratory, eye and skin irritation. Corrosive to some metals. |
Sodium Fluoride Synthesis Methods
Chemists use several methods to synthesize sodium fluoride (NaF).
One common method involves reacting hydrofluoric acid with sodium hydroxide or sodium carbonate. To remove any water or impurities, someone dries and heats the resulting product.
Another method involves the reaction of NaCl with HF, which produces NaF and hydrogen chloride as byproducts. This method is less common due to safety concerns associated with the handling of hydrogen fluoride.
Another way to synthesize NaF is through the reaction of sodium carbonate with HF gas. The reaction produces NaF, carbon dioxide, and water vapor. Industrial applications commonly use this method to produce NaF.
Furthermore, one can synthesize NaF by heating fluorine gas with sodium metal. However, this method is uncommon because of the high reactivity of both sodium and fluorine. Additionally, this method requires specialized equipment and careful handling due to the risk of explosion.
Sodium Fluoride Uses
NaF has several uses across different industries. Here are some common uses of NaF:
- Dental hygiene: Toothpaste, mouthwash, and dental treatments add NaF to prevent dental caries and improve oral health.
- Water treatment: Added to drinking water in some regions to prevent tooth decay.
- Industrial applications: Used as a flux in the production of aluminum, and in the production of glass and ceramics to lower the melting point and improve the transparency.
- Metallurgy: Used in the refining and processing of metals, such as in the removal of impurities in the production of steel and aluminum.
- Pesticide: Used as a pesticide in the control of rodents and insects.
- Chemistry: Used as a source of fluoride ions in various chemical reactions.
- Nuclear industry: Used as a coolant and heat transfer agent in some nuclear reactors.
- Pharmaceuticals: Used in the manufacturing of certain medications, such as antidepressants and anti-inflammatory drugs.
Questions:
Q: Is sodium fluoride in toothpaste bad for you?
A: NaF in toothpaste is generally considered safe when used as directed. It helps prevent tooth decay and is approved by dental associations worldwide. However, excessive ingestion of toothpaste can lead to stomach upset and other health problems.
Q: Would a dilute or concentrated sodium fluoride solution have a higher boiling point?
A: A concentrated NaF solution would have a higher boiling point than a dilute solution due to the increased number of solute particles in the solution, which raises the boiling point through the boiling point elevation effect.
Q: How many grams are in 4.5 moles of sodium fluoride?
A: The molar mass of NaF is 41.99 g/mol, so 4.5 moles of NaF would be equivalent to 188.96 grams.
Q: Is sodium fluoride ionic or covalent?
A: NaF is an ionic compound, formed by the electrostatic attraction between the Na+ ion and F- ion.
Q: What is the correct way to represent the ionic compound sodium fluoride?
A: The correct way to represent this ionic compound is NaF, where Na represents the Na+ and F represents the F-.
Q: What is the name of the compound with the formula NaF?
A: The name for the compound with the formula NaF is sodium fluoride.
Q: Is NaF an acid or base?
A: NaF is a salt, formed from the neutralization reaction between a strong base (sodium hydroxide) and a weak acid (hydrofluoric acid). It is neither an acid nor a base, but it can undergo hydrolysis to form a basic solution.