| IUPAC name |
3D model (JSmol)
CompTox Dashboard (EPA)
|Molar mass||349.012 g/mol |
|Appearance||yellow oily liquid |
|Density||3.2 g⋅cm−3 |
|Melting point||−15 °C (5 °F; 258 K)  stable below 0 °C (32 °F; 273 K) |
|Boiling point||50 °C (122 °F; 323 K)  decomposes|
Std enthalpy of
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Lead tetrachloride, also known as lead(IV) chloride, has the molecular formula PbCl4. It is a yellow, oily liquid which is stable below 0 °C, and decomposes at 50 °C.  It has a tetrahedral configuration, with lead as the central atom. The Pb–Cl covalent bonds have been measured to be 247 pm and the bond energy is 243 kJ⋅mol−1. 
Lead tetrachloride can be made by reacting lead(II) chloride PbCl2, and hydrochloric acid HCl, in the presence of chlorine gas (Cl2),  leading to the formation of chloroplumbic acid H2PbCl6. It is then converted to the ammonium salt (NH4)2PbCl6 by adding ammonium chloride (NH4Cl). Finally, the solution is treated with concentrated sulfuric acid H2SO4, to separate out lead tetrachloride. This series of reactions is conducted at 0 °C. The following equations illustrate the reaction:
Unlike carbon tetrachloride, another group IV (IUPAC: group 14) chloride, lead tetrachloride reacts with water. This is because the central atom is bigger (Pb is bigger than C) so there is less cluttering and water can easily access it.  Also, because of the presence of empty d orbitals on the Pb atom, oxygen can bind to it before a Pb–Cl bond has to break, thus requiring less energy. The overall reaction is thus as follow:
Lead tetrachloride tends to decompose further into lead dichloride and chlorine gas: 
There are reports that this reaction can proceed explosively and that the compound is best stored under pure sulfuric acid at -80 °C in the dark. 
The stability of the +4 oxidation state decreases as we travel down this group of the periodic table.  Thus while carbon tetrachloride is a stable compound, with lead the oxidation state +2 is favored and PbCl4 quickly becomes PbCl2. Indeed, the inert pair effect causes lead to favor its +2 oxidation state: Pb atom loses all its outermost p electrons and ends up with a stable, filled s subshell. 
Lead is a cumulative poison.  Only limited evidence have been shown of lead's carcinogenic effect, but lead tetrachloride, as well as all other lead compounds, is "reasonably anticipated to be human carcinogens" according to the Report on Carcinogens, Twelfth Edition (2011).  Lead can be absorbed by the body through several routes, primarily inhalation but also ingestion and dermal contact. Lead compounds are also teratogens. 
Chlorine is a chemical element with the symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. Chlorine is a yellow-green gas at room temperature. It is an extremely reactive element and a strong oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity on the revised Pauling scale, behind only oxygen and fluorine. On several scales other than the revised Pauling scale, nitrogen's electronegativity is also listed as greater than chlorine's, such as on the Allen, Allred-Rochow, Martynov-Batsanov, Mulliken-Jaffe, Nagle, and Noorizadeh-Shakerzadeh electronegativity scales.
In chemistry, a salt is a chemical compound consisting of an ionic assembly of positively charged cations and negatively charged anions, which results in a compound with no net electric charge. A common example is table salt, with positively charged sodium ions and negatively charged chloride ions.
Aqua regia is a mixture of nitric acid and hydrochloric acid, optimally in a molar ratio of 1:3. Aqua regia is a fuming liquid. Freshly prepared aqua regia is colorless, but it turns yellow, orange or red within seconds due to the formation of nitrosyl chloride and nitrogen dioxide. It was named by alchemists because it can dissolve the noble metals gold and platinum, though not all metals.
The chlorite ion, or chlorine dioxide anion, is the halite with the chemical formula of ClO−
2. A chlorite (compound) is a compound that contains this group, with chlorine in the oxidation state of +3. Chlorites are also known as salts of chlorous acid.
Sodium hypochlorite is an inorganic chemical compound with the formula NaOCl, comprising a sodium cation and a hypochlorite anion. It may also be viewed as the sodium salt of hypochlorous acid. The anhydrous compound is unstable and may decompose explosively. It can be crystallized as a pentahydrate NaOCl·5H
2O, a pale greenish-yellow solid which is not explosive and is stable if kept refrigerated.
The compound hydrogen chloride has the chemical formula HCl and as such is a hydrogen halide. At room temperature, it is a colourless gas, which forms white fumes of hydrochloric acid upon contact with atmospheric water vapor. Hydrogen chloride gas and hydrochloric acid are important in technology and industry. Hydrochloric acid, the aqueous solution of hydrogen chloride, is also commonly given the formula HCl.
Dinitrogen pentoxide is the chemical compound with the formula N2O5, also known as nitrogen pentoxide or nitric anhydride. It is one of the binary nitrogen oxides, a family of compounds that only contain nitrogen and oxygen. It exists as colourless crystals that melt at 41 °C. Its boiling point is 47 °C, and sublimes slightly above room temperature, yielding a colorless gas.
Phosphorus trichloride is an inorganic compound with the chemical formula PCl3. A colorless liquid when pure, it is an important industrial chemical, being used for the manufacture of phosphites and other organophosphorus compounds. It is toxic and reacts readily with water to release hydrogen chloride.
Dichlorine heptoxide is the chemical compound with the formula Cl2O7. This chlorine oxide is the anhydride of perchloric acid. It is produced by the careful distillation of perchloric acid in the presence of the dehydrating agent phosphorus pentoxide:
Chlorous acid is an inorganic compound with the formula HClO2. It is a weak acid. Chlorine has oxidation state +3 in this acid. The pure substance is unstable, disproportionating to hypochlorous acid (Cl oxidation state +1) and chloric acid (Cl oxidation state +5):
Sulfamic acid, also known as amidosulfonic acid, amidosulfuric acid, aminosulfonic acid, sulphamic acid and sulfamidic acid, is a molecular compound with the formula H3NSO3. This colourless, water-soluble compound finds many applications. Sulfamic acid melts at 205 °C before decomposing at higher temperatures to water, sulfur trioxide, sulfur dioxide and nitrogen.
A direct combination reaction (also known as a synthesis reaction) is a reaction where two or more elements or compounds (reactants) combine to form a single compound (product). Such reactions are represented by equations of the following form: X + Y → XY (A+B → AB). The combination of two or more elements to form one compound is called a combination reaction. In other words, when two or more elements or compounds react so as to form one single compound, then the chemical reaction that takes place is called a combination reaction. | a)- Between elements | C + O2 → CO2 | Carbon completely burnt in oxygen yields carbon dioxide |- | b) Between compounds | CaO + H2O → Ca(OH)2 | Calcium oxide (lime) combined with water gives calcium hydroxide (slaked lime) |- | c) Between elements and compounds | 2CO + O2 → 2CO2 | Oxygen combines with carbon monoxide,And carbon dioxide is formed. |}
Terbium(III,IV) oxide, occasionally called tetraterbium heptaoxide, has the formula Tb4O7, though some texts refer to it as TbO1.75. There is some debate as to whether it is a discrete compound, or simply one phase in an interstitial oxide system. Tb4O7 is one of the main commercial terbium compounds, and the only such product containing at least some Tb(IV) (terbium in the +4 oxidation state), along with the more stable Tb(III). It is produced by heating the metal oxalate, and it is used in the preparation of other terbium compounds. Terbium forms three other major oxides: Tb2O3, TbO2, and Tb6O11.
Sulfuryl chloride is an inorganic compound with the formula SO2Cl2. At room temperature, it is a colorless liquid with a pungent odor. Sulfuryl chloride is not found in nature, as can be inferred from its rapid hydrolysis.
Monochloramine, often called chloramine, is the chemical compound with the formula NH2Cl. Together with dichloramine (NHCl2) and nitrogen trichloride (NCl3), it is one of the three chloramines of ammonia. It is a colorless liquid at its melting point of −66 °C (−87 °F), but it is usually handled as a dilute aqueous solution, in which form it is sometimes used as a disinfectant. Chloramine is too unstable to have its boiling point measured.
Barium chlorate, Ba(ClO3)2, is the barium salt of chloric acid. It is a white crystalline solid, and like all soluble barium compounds, irritant and toxic. It is sometimes used in pyrotechnics to produce a green color. It also finds use in the production of chloric acid.
Germanium dichloride is a chemical compound of germanium and chlorine with the formula GeCl2. It is a solid and contains germanium in the +2 oxidation state.
Compounds of lead exist with lead in two main oxidation states: +2 and +4. The former is more common. Inorganic lead(IV) compounds are typically strong oxidants or exist only in highly acidic solutions.
Protactinium compounds are compounds containing the element protactinium. These compounds usually have protactinium in the +5 oxidation state, although these compounds can also exist in the +2, +3 and +4 oxidation states.