Difference between revisions of "Lead(II) nitrate"

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'''Lead(II) nitrate''' is the inorganic compound with chemical formula '''Pb(NO<sub>3</sub>)<sub>2</sub>''', and is one of the few examples of a water-soluble [[lead]] compound.
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'''Lead(II) nitrate''' is the inorganic compound with chemical formula '''Pb(NO<sub>3</sub>)<sub>2</sub>''', and is one of the few examples of a water-soluble [[lead]] compound, though it's not as often used due to its tendency to hydrolyze in neutral conditions.
  
 
==Properties==
 
==Properties==
 
===Chemical===
 
===Chemical===
 
Lead nitrate is prone to partial hydrolysis in water, giving neutral solutions a cloudy appearance. This can be rectified by the addition of a small amount of [[nitric acid]] to the solution. Given that lead nitrate is the most commonly encountered water-soluble lead salt, it is an important precursor to other insoluble lead compounds.
 
Lead nitrate is prone to partial hydrolysis in water, giving neutral solutions a cloudy appearance. This can be rectified by the addition of a small amount of [[nitric acid]] to the solution. Given that lead nitrate is the most commonly encountered water-soluble lead salt, it is an important precursor to other insoluble lead compounds.
 +
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Lead oxide can be used in flash powders, but this is rarely done, as the combustion releases airborne particles of toxic lead oxide.
  
 
===Physical===
 
===Physical===
Lead nitrate generally appears as colorless or white crystals or powder, often with a dusty-looking outer surface. Lead nitrate is one of very few compounds of lead that is soluble in water. Even so, it is difficult to dissolve, often requiring a lot of stirring or heating to finally enter solution.
+
Lead nitrate generally appears as colorless or white crystals or powder, often with a dusty-looking outer surface. Lead nitrate is one of very few compounds of lead that is soluble in water. Even so, it is difficult to dissolve, often requiring a lot of stirring or heating to finally enter solution. It tends to slightly hydrolyze in neutral solutions, usually a small amount of nitric acid is added to keep all the compound dissolved.
  
 
==Availability==
 
==Availability==
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==Preparation==
 
==Preparation==
Lead nitrate is slowly formed by the reaction between [[nitric acid]] and [[lead]] metal, and can also be produced at a much faster rate by dissolving lead oxides in nitric acid.
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Lead nitrate is slowly formed by the reaction between [[nitric acid]] and [[lead]] metal, and can also be produced at a much faster rate and in better yield by dissolving [[lead oxide]]s or lead hydroxide/carbonate in nitric acid.
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: 3 Pb + 8 HNO<sub>3</sub> → 3 Pb(NO<sub>3</sub>)<sub>2</sub> + 2 NO + 4 H<sub>2</sub>O
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 +
: PbO + 2 HNO<sub>3</sub> → Pb(NO<sub>3</sub>)<sub>2</sub> + H<sub>2</sub>O
 +
 
 +
: Pb(OH)<sub>2</sub> + 2 HNO<sub>3</sub> → Pb(NO<sub>3</sub>)<sub>2</sub> + 2 H<sub>2</sub>O
 +
 
 +
: PbCO<sub>3</sub> + 2 HNO<sub>3</sub> → Pb(NO<sub>3</sub>)<sub>2</sub> + H<sub>2</sub>O + CO<sub>2</sub>
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 +
An excess amount of acid is used to prevent hydrolysis. The compound is extracted via recrystallization.
  
 
==Projects==
 
==Projects==
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===Storage===
 
===Storage===
Lead nitrate is relatively unreactive and can be stored indefinitely, preferably in a labeled, difficult-to-open container to avoid accidental poisonings. However it is somewhat sensitive to water over time, so it's best to store it in a dry sealed container.
+
Lead nitrate is relatively unreactive and can be stored almost indefinitely, preferably in a labeled, difficult-to-open container to avoid accidental poisonings. However it is somewhat sensitive to water over time, so it's best to store it in a dry sealed container.
 +
 
 +
It is much more stable in solution, with a small amount of nitric acid added.
  
 
===Disposal===
 
===Disposal===

Revision as of 18:58, 27 July 2018

Lead(II) nitrate
Names
IUPAC name
Lead(II) nitrate
Other names
Lead dinitrate
Lead nitrate
Plumb dulcis
Plumbous nitrate
Properties
Pb(NO3)2
Molar mass 331.2 g/mol
Appearance White solid
Density 4.53 g/cm3 (20 °C)
Melting point 470 °C (878 °F; 743 K) (decomposes)
Boiling point Decomposes
37.65 g/100 ml (0 °C)
59.7 g/100 ml (25 °C)
127 g/100 ml (100 °C)
Solubility Insoluble in conc. nitric acid
Solubility in ethanol 0.04 g/100 ml
Solubility in methanol 1.3 g/100 ml
Vapor pressure ~0 mmHg
Hazards
Safety data sheet Sigma-Aldrich
Flash point Non-flammable
Related compounds
Related compounds
Lead(II) acetate
Lead(II) azide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Lead(II) nitrate is the inorganic compound with chemical formula Pb(NO3)2, and is one of the few examples of a water-soluble lead compound, though it's not as often used due to its tendency to hydrolyze in neutral conditions.

Properties

Chemical

Lead nitrate is prone to partial hydrolysis in water, giving neutral solutions a cloudy appearance. This can be rectified by the addition of a small amount of nitric acid to the solution. Given that lead nitrate is the most commonly encountered water-soluble lead salt, it is an important precursor to other insoluble lead compounds.

Lead oxide can be used in flash powders, but this is rarely done, as the combustion releases airborne particles of toxic lead oxide.

Physical

Lead nitrate generally appears as colorless or white crystals or powder, often with a dusty-looking outer surface. Lead nitrate is one of very few compounds of lead that is soluble in water. Even so, it is difficult to dissolve, often requiring a lot of stirring or heating to finally enter solution. It tends to slightly hydrolyze in neutral solutions, usually a small amount of nitric acid is added to keep all the compound dissolved.

Availability

Due to the high toxicity of lead compounds, especially those that are water-soluble, it is unlikely that lead nitrate has any over-the-counter sources. Lead metal, however, is easily obtainable and can be used to produce it if nitric acid is available.

Preparation

Lead nitrate is slowly formed by the reaction between nitric acid and lead metal, and can also be produced at a much faster rate and in better yield by dissolving lead oxides or lead hydroxide/carbonate in nitric acid.

3 Pb + 8 HNO3 → 3 Pb(NO3)2 + 2 NO + 4 H2O
PbO + 2 HNO3 → Pb(NO3)2 + H2O
Pb(OH)2 + 2 HNO3 → Pb(NO3)2 + 2 H2O
PbCO3 + 2 HNO3 → Pb(NO3)2 + H2O + CO2

An excess amount of acid is used to prevent hydrolysis. The compound is extracted via recrystallization.

Projects

  • Make the bright yellow pigment chrome yellow (lead(II) chromate)
  • Make lead dioxide (for Ti/PbO2 electrode)
  • Make lead(II) azide

Handling

Safety

Lead nitrate, like other lead compounds, is highly toxic and is a cumulative poison that accumulates in the body. Being water-soluble, it is even more so, and should always be handled with gloves and skin protection, and the very strictest of measures should be taken to prevent its ingestion.

Storage

Lead nitrate is relatively unreactive and can be stored almost indefinitely, preferably in a labeled, difficult-to-open container to avoid accidental poisonings. However it is somewhat sensitive to water over time, so it's best to store it in a dry sealed container.

It is much more stable in solution, with a small amount of nitric acid added.

Disposal

All water-soluble lead salts should be dissolved in water and converted to lead carbonate or oxides, which are safer to handle. If the lead must be gotten rid of, these insoluble compounds should be taken to a facility that processes hazardous wastes.

References

Relevant Sciencemadness threads