Difference between revisions of "Sodium fluoride"
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(Created page with "{{Chembox | Name = Sodium fluoride | Reference = | IUPACName = Sodium fluoride | PIN = | SystematicName = | OtherNames = Florocid <!-- Images --> | ImageFile = | ImageSize =...") |
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| Line 49: | Line 49: | ||
| Appearance = White solid | | Appearance = White solid | ||
| BoilingPt = | | BoilingPt = | ||
| − | | BoilingPtC = | + | | BoilingPtC = 1,704 |
| BoilingPt_ref = | | BoilingPt_ref = | ||
| BoilingPt_notes = | | BoilingPt_notes = | ||
| − | | Density = | + | | Density = 2.558 g/cm<sup>3</sup> |
| Formula = NaF | | Formula = NaF | ||
| HenryConstant = | | HenryConstant = | ||
| Line 58: | Line 58: | ||
| MolarMass = 41.988173 g/mol | | MolarMass = 41.988173 g/mol | ||
| MeltingPt = | | MeltingPt = | ||
| − | | MeltingPtC = | + | | MeltingPtC = 993 |
| MeltingPt_ref = | | MeltingPt_ref = | ||
| MeltingPt_notes = | | MeltingPt_notes = | ||
| Odor = Odorless | | Odor = Odorless | ||
| − | | pKa = | + | | pKa = 7.4 |
| pKb = | | pKb = | ||
| − | | Solubility = | + | | Solubility = 3.64 g/100 ml (0 °C)<br>4.04 g/100 ml (20 °C)<br>5.05 g/100 ml (100 °C) |
| − | | SolubleOther = | + | | SolubleOther = Reacts with [[sulfuric acid]]<br>Slightly soluble in [[ammonia]], [[hydrofluoric acid]]<br>Negligible in [[acetone]], [[dimethylformamide]], [[ethanol]], [[methanol]], liq. [[sulfur dioxide|SO<sub>2</sub>]]<br>Insoluble in halocarbons, hydrocarbons |
| Solvent = | | Solvent = | ||
| − | | VaporPressure = | + | | VaporPressure = ~0 mmHg |
}} | }} | ||
| Section3 = {{Chembox Structure | | Section3 = {{Chembox Structure | ||
| Coordination = | | Coordination = | ||
| − | | CrystalStruct = | + | | CrystalStruct = Cubic |
| − | | MolShape = | + | | MolShape = Octahedral |
}} | }} | ||
| Section4 = {{Chembox Thermochemistry | | Section4 = {{Chembox Thermochemistry | ||
| − | | DeltaGf = | + | | DeltaGf = -543.3 kJ/mol |
| DeltaHc = | | DeltaHc = | ||
| − | | DeltaHf = | + | | DeltaHf = -573.6 kJ/mol |
| − | | Entropy = | + | | Entropy = 51.3 J·mol<sup>−1</sup>·K<sup>−1</sup> |
| − | | HeatCapacity = | + | | HeatCapacity = 46.82 J·mol<sup>−1</sup>·K<sup>−1</sup> |
}} | }} | ||
| Section5 = {{Chembox Explosive | | Section5 = {{Chembox Explosive | ||
| Line 88: | Line 88: | ||
}} | }} | ||
| Section6 = {{Chembox Hazards | | Section6 = {{Chembox Hazards | ||
| − | | AutoignitionPt = | + | | AutoignitionPt = Non-flammable |
| − | | ExploLimits = | + | | ExploLimits = Non-explosive |
| − | | ExternalMSDS = | + | | ExternalMSDS = [https://www.docdroid.net/vWzhs9X/sodium-fluoride-sa.pdf Sigma-Aldrich] |
| − | | FlashPt = | + | | FlashPt = Non-flammable |
| − | | LD50 = | + | | LD50 = 52–200 mg/kg (oral in rats, mice, rabbits) |
| LC50 = | | LC50 = | ||
| − | | MainHazards = | + | | MainHazards = Toxic |
| NFPA-F = | | NFPA-F = | ||
| NFPA-H = | | NFPA-H = | ||
| Line 113: | Line 113: | ||
===Chemical=== | ===Chemical=== | ||
Addition of a strong acid, like [[sulfuric acid]] will release hydrofluoric acid. | Addition of a strong acid, like [[sulfuric acid]] will release hydrofluoric acid. | ||
| + | |||
| + | : 2 NaF + H<sub>2</sub>SO<sub>4</sub> → 2 HF + Na<sub>2</sub>SO<sub>4</sub> | ||
===Physical=== | ===Physical=== | ||
| − | Sodium fluoride is a white solid, soluble in water. | + | Sodium fluoride is a white solid, poorly soluble in water. |
==Availability== | ==Availability== | ||
| Line 123: | Line 125: | ||
==Preparation== | ==Preparation== | ||
| − | Can be prepared by neutralizing hydrofluoric acid with a base, like sodium hydroxide, sodium carbonate or sodium bicarbonate. | + | Can be prepared by neutralizing hydrofluoric acid with a base, like [[sodium hydroxide]], [[sodium carbonate]] or [[sodium bicarbonate]]. |
| + | |||
| + | : HF + NaOH → NaF + H<sub>2</sub>O | ||
| + | : 2 HF + Na<sub>2</sub>CO<sub>3</sub> → 2 NaF + H<sub>2</sub>O + CO<sub>2</sub> | ||
| + | : HF + NaHCO<sub>3</sub> → NaF + H<sub>2</sub>O + CO<sub>2</sub> | ||
| + | |||
| + | Due to its poor solubility, sodium fluoride will precipitate out of the solution. | ||
==Projects== | ==Projects== | ||
| Line 135: | Line 143: | ||
===Storage=== | ===Storage=== | ||
| − | In closed plastic bottles. | + | In closed plastic (PE or PP) bottles. Avoid storing it in glass containers. |
===Disposal=== | ===Disposal=== | ||
| Line 143: | Line 151: | ||
<references/> | <references/> | ||
===Relevant Sciencemadness threads=== | ===Relevant Sciencemadness threads=== | ||
| + | *[http://www.sciencemadness.org/talk/viewthread.php?tid=72030 Fluorides from PTFE] | ||
| + | *[http://www.sciencemadness.org/talk/viewthread.php?tid=13524 fluoride from toothpaste?] | ||
| + | *[http://www.sciencemadness.org/talk/viewthread.php?tid=2424 Sodium fluoride attacks glass?] | ||
| + | *[http://www.sciencemadness.org/talk/viewthread.php?tid=22229 sodium fluoride from calcium fluoride and sodium phosphate] | ||
| + | |||
| + | [[Category:Chemical compounds]] | ||
| + | [[Category:Inorganic compounds]] | ||
| + | [[Category:Sodium compounds]] | ||
| + | [[Category:Fluorides]] | ||
| + | [[Category:Minerals]] | ||
| + | [[Category:Halides]] | ||
Revision as of 12:18, 17 August 2018
| Names | |
|---|---|
| IUPAC name
Sodium fluoride
| |
| Other names
Florocid
| |
| Properties | |
| NaF | |
| Molar mass | 41.988173 g/mol |
| Appearance | White solid |
| Odor | Odorless |
| Density | 2.558 g/cm3 |
| Melting point | 993 °C (1,819 °F; 1,266 K) |
| Boiling point | 1,704 °C (3,099 °F; 1,977 K) |
| 3.64 g/100 ml (0 °C) 4.04 g/100 ml (20 °C) 5.05 g/100 ml (100 °C) | |
| Solubility | Reacts with sulfuric acid Slightly soluble in ammonia, hydrofluoric acid Negligible in acetone, dimethylformamide, ethanol, methanol, liq. SO2 Insoluble in halocarbons, hydrocarbons |
| Vapor pressure | ~0 mmHg |
| Acidity (pKa) | 7.4 |
| Thermochemistry | |
| Std molar
entropy (S |
51.3 J·mol−1·K−1 |
| Std enthalpy of
formation (ΔfH |
-573.6 kJ/mol |
| Hazards | |
| Safety data sheet | Sigma-Aldrich |
| Flash point | Non-flammable |
| Lethal dose or concentration (LD, LC): | |
| LD50 (Median dose)
|
52–200 mg/kg (oral in rats, mice, rabbits) |
| Related compounds | |
| Related compounds
|
Sodium chloride Sodium bromide Sodium iodide |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
Sodium fluoride is an inorganic compound with the formula NaF, a salt of hydrofluoric acid.
Contents
Properties
Chemical
Addition of a strong acid, like sulfuric acid will release hydrofluoric acid.
- 2 NaF + H2SO4 → 2 HF + Na2SO4
Physical
Sodium fluoride is a white solid, poorly soluble in water.
Availability
Sodium fluoride is sold by chemical suppliers.
It occurs in nature as the rare mineral villiaumite.
Preparation
Can be prepared by neutralizing hydrofluoric acid with a base, like sodium hydroxide, sodium carbonate or sodium bicarbonate.
- HF + NaOH → NaF + H2O
- 2 HF + Na2CO3 → 2 NaF + H2O + CO2
- HF + NaHCO3 → NaF + H2O + CO2
Due to its poor solubility, sodium fluoride will precipitate out of the solution.
Projects
- Make hydrofluoric acid
- Make fluorocarbons
- Mineral collecting (villiaumite)
Handling
Safety
Avoid contact with strong acids, as it will release hydrofluoric acid.
Storage
In closed plastic (PE or PP) bottles. Avoid storing it in glass containers.
Disposal
Should be converted to the less soluble calcium fluoride and dumped in trash. Recycling is also an option.
