Lead(II) chromate

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Lead(II) chromate
Other names	chrome yellow chrome orange plumbous chromate
Identifiers
CAS number	[7758-97-6]
Properties
Molecular formula	PbCrO₄
Molar mass	323.2 g/mol
Appearance	orange-yellow powder
Density	6.3 g/cm³, solid
Melting point	844°C
Solubility in water	negligible
Hazards
MSDS	External MSDS
EU classification	not listed
NFPA 704	0 3 0
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Lead(II) chromate (Pb Cr O₄) is a chemical compound. It has a vivid yellow color and is practically insoluble in water, and as a result, is used in paints under the name "chrome yellow". Previously, its use was wider. It and "white lead", or lead(II) carbonate, were the most common lead-based paint pigments. It is commonly made in the laboratory by reacting a lead(II) salt (such as lead(II) nitrate) with a chromate or dichromate salt (such as potassium chromate or potassium dichromate) in solution in water, producing a very deep yellow to orange precipitate of lead(II) chromate.

Lead (II) Chromate may also be known as chrome yellow, chromic acid lead (II) salt, canary chrome yellow 40-2250, chrome green, chrome green UC61, chrome green UC74, chrome green UC76, chrome lemon, crocoite, dianichi chrome yellow G, lemon yellow, king's yellow, Leipzig yellow, lemon yellow, Paris yellow, pigment green 15, plumbous chromate, pure lemon chrome L3GS, and various other names.

Conditions/substances to avoid are: strong reducing agents, combustibles and organic materials.

Due to containing both lead and hexavalent chromium, lead(II) chromate is profoundly toxic.

Lead(II) chromate is used in some pyrotechnic compositions, especially delay compositions, as an oxidizer.

1 Reactions
2 Dangers of lead (II) chromate
- 2.1 If swallowed
- 2.2 If inhaled
3 References

[edit] Reactions

Heating in hydroxide solution produces chrome red, a red or orange powder made by PbO and CrO₃.

Also, in hydroxide solution lead chromate partially dissolves forming plumbite complex.

PbCrO₄ + 4 OH^- → [Pb(OH)₄]^2- + CrO₄^2-

[edit] Dangers of lead (II) chromate

Lead (II) chromate is a poison, and can be fatal if swallowed or inhaled.

Lead (II) chromate is a known carcinogen, developmental toxicant, and reproductive toxicant. It is also suspected that lead (II) chromate is a cardivascular or blood toxicant, immunotoxicant, kidney toxicant, neurotoxicant, respiratory toxicant, and a skin toxicant or sense organ toxicant.

[edit] If swallowed

If swallowed, lead (II) chromate poisoning can lead to abdominal pain and spasms, nausea, vomiting, and headaches. If the poisoning is not severe, you may experience lead line on the gums, a metallic taste, muscle weakness, and dizziness. The symptoms appear to get worse as the poisoning becomes more severe. Severe poisoning can lead to a coma and even death.

[edit] If inhaled

If inhaled, and the poisoning is not severe, you may experience symptoms such as a sore throat, coughing, shortness of breath, and labored breathing. Severe poisoning may lead to pulmonary edema, as well as several symptoms experienced from indigestion