Search results
Results From The WOW.Com Content Network
Lead perchlorate trihydrate is produced by the reaction of lead(II) oxide, lead carbonate, or lead nitrate by perchloric acid: . Pb(NO 3) 2 + HClO 4 → Pb(ClO 4) 2 + HNO 3. The excess perchloric acid was removed by first heating the solution to 125 °C, then heating it under moist air at 160 °C to remove the perchloric acid by converting the acid to the dihydrate.
It is then converted to the ammonium salt (NH 4) 2 PbCl 6 by adding ammonium chloride (NH 4 Cl). Finally, the solution is treated with concentrated sulfuric acid H 2 SO 4, to separate out lead tetrachloride. This series of reactions is conducted at 0 °C. The following equations illustrate the reaction: PbCl 2 + 2HCl + Cl 2 → H 2 PbCl 6
Nonpolar bonds generally occur when the difference in electronegativity between the two atoms is less than 0.5; Polar bonds generally occur when the difference in electronegativity between the two atoms is roughly between 0.5 and 2.0; Ionic bonds generally occur when the difference in electronegativity between the two atoms is greater than 2.0
Pb is used in HCl service even though the PbCl 2 formed is slightly soluble in HCl. Addition of 6–25% of antimony (Sb) increases corrosion resistance. [16] A basic chloride of lead, PbCl 2 ·Pb(OH) 2, is known as Pattinson's white lead and is used as pigment in white paint. [17]
Lead(II) sulfate is poorly soluble, as can be seen in the following diagram showing addition of SO 2− 4 to a solution containing 0.1 M of Pb 2+. The pH of the solution is 4.5, as above that, Pb 2+ concentration can never reach 0.1 M due to the formation of Pb(OH) 2. Observe that Pb 2+ solubility drops 10,000 fold as SO 2− 4 reaches 0.1 M.
A perchlorate is a chemical compound containing the perchlorate ion, ClO − 4, the conjugate base of perchloric acid (ionic perchlorate). As counterions, there can be metal cations , quaternary ammonium cations or other ions, for example, nitronium cation ( NO + 2 ).
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
Chlorate is the common name of the ClO − 3 anion, whose chlorine atom is in the +5 oxidation state.The term can also refer to chemical compounds containing this anion, with chlorates being the salts of chloric acid.