How Is Lead IV Oxide (PbO₂) Produced and Applied in Chemistry?
What is Lead IV Oxide?
The PbO2 or lead IV oxide is the formula of an oxide in which the oxidation state of lead is +4. It is also referred to as anhydrous Plumbic acid or lead dioxide or Plumbic oxide. It is considered to be a strong oxidising agent. However, Plumbic oxide does not dissolve in alcohol or water and stays insoluble in these liquids. It is a dark brown colour crystalline powder and is extensively used in making electrodes, explosives, and match sticks. This dark brown powder dissolves in Hydrochloric acid, nitric acid, oxalic acid, and many other acids. PbO2 is also used in the manufacturing procedure of rubber alternates.
Properties of Lead IV Oxide PbO2
Physical Properties
PbO2 is a dark brown or black colour crystalline powder.
The molar mass of lead IV oxide is 239.1988g/mol
Lead oxide does not dissolve in the water and alcohol but is soluble in most of the acid.
This crystalline powder's melting point is 290°C or 554°F or 563K.
Lead oxide has a density of 9.38g/cm³
Lead stands in three oxidation states: Pb (0), metal form, Pb (II), and Pb (IV). Lead naturally exists in Pb(II) form in our environment, and Pb(IV) is created under extremely oxidising conditions. Inorganic compounds Pb(IV) do not exist in the environment and are created for manufacturing explosives, and match sticks.
Lead IV Oxide Structure PbO2
Lead's exact mass and monoisotopic mass is 239.966 g/mol. In Lead oxide structure, hydrogen bond acceptors are two in number whereas the number of hydrogen bond donors stands at zero. This compound has one covalently bonded unit and is canonicalised.
PbO2 Uses Lead IV Oxide
It is extensively used in manufacturing explosives
Lead IV Oxide is used in the manufacturing of dyes as an oxidising agent
It is employed as a curing agent for polysulfide
In electrochemistry, it is used as an anode material
Lead is used to electrolyte copper to prevent it from corrosion.
Textile industries employ lead oxide as an oxidising agent
It is also used in lead-acid storage batteries
Lead oxide is also used as an analytical reagent
To manufacture rubber substitutes lead oxide is used
It is also used in making lightning arresters
Production of Lead IV Oxide
The lead dioxide and lead oxide films can be obtained by various techniques like thermal evaporation, laser-assisted deposition, metal-organic CVD, atomic layer epitaxy, and exposing lead films to oxygen or RF oxygen plasma. However, the majority of these techniques use preformed lead oxide to put it in thin layers. Some of the techniques like MOCVD and ALD use precursor chemistry to deposit thin films.
The reaction of red lead with nitric acid also produces lead oxide.
Pb3O4+ 4HNO3 - PbO2+2Pb(NO3)2+ 2 H2O
Solved Questions
Q: What is the Lead IV Oxide Chemical Formula?
Ans: The chemical formula for Lead IV Oxide is PbO2.
Q: What is Lead IV Oxide Decomposition Formula?
Ans: The lead oxide decomposes upon heating in the atmosphere is as follows.
24PbO2- 2Pb12 O19+ 5O
Q: How is Lead Oxide Obtained?
Ans: PbO2 is a corrosion outcome that can evolve in lead pipes that are used for drinking water and the stability can regulate lead concentration in the water. It is obtained only by heating lead oxide in the air. By heating lead under pure oxygen there will be no impurity that will come out and hence there will be no corrosion.
FAQs on Lead IV Oxide (PbO₂): Structure, Properties & Uses
1. What is Lead (IV) Oxide, and what is its chemical formula?
Lead (IV) Oxide is an inorganic compound where lead has an oxidation state of +4. Its chemical formula is PbO₂. It is also commonly known as lead dioxide or plumbic oxide. It typically appears as a dark-brown or black powder and is insoluble in water.
2. What are the most common real-world uses of Lead (IV) Oxide?
Lead (IV) Oxide is a strong oxidizing agent, which makes it useful in various applications. Its main uses include:
- Lead-acid Batteries: It serves as the cathode (positive electrode) in rechargeable car batteries.
- Manufacturing: It is used in the production of matches, fireworks, and certain dyes.
- Electrochemistry: It is used as an anode material in electrosynthesis processes due to its ability to resist corrosion.
3. How is Lead (IV) Oxide typically prepared?
Lead (IV) Oxide can be prepared through several methods. A common laboratory method involves the oxidation of a lead(II) compound. For instance, reacting lead(II) acetate with calcium hypochlorite (a bleaching agent) will produce a precipitate of PbO₂. Commercially, it is often prepared by the anodic oxidation of lead(II) sulphate in an acidic medium.
4. Why is the compound called Lead (IV) Oxide if the formula is just PbO₂?
This is a great question that relates to chemical naming rules. The Roman numeral '(IV)' in the name indicates the oxidation state of the lead (Pb) atom, which is +4. In the PbO₂ molecule, each oxygen atom has an oxidation state of -2. To make the compound electrically neutral, one lead atom must have a +4 charge to balance the two oxygen atoms (-2 x 2 = -4). Therefore, the name reflects the charge, not the number of atoms.
5. What is the key difference between Lead (II) Oxide (PbO) and Lead (IV) Oxide (PbO₂)?
The primary difference lies in the oxidation state of the lead atom and their resulting chemical properties:
- Oxidation State: In PbO, lead is in its more stable +2 oxidation state. In PbO₂, lead is in its less stable +4 oxidation state.
- Chemical Nature: Because the +4 state is less stable, PbO₂ is a powerful oxidizing agent (it wants to gain electrons to become Pb²⁺). PbO is largely amphoteric and less reactive.
- Colour: PbO can be red or yellow, whereas PbO₂ is typically a dark brown or black solid.
6. Why is Lead (IV) Oxide considered a strong oxidising agent?
Lead (IV) Oxide is a strong oxidising agent due to the 'inert pair effect'. For heavy elements in the p-block like lead, the +2 oxidation state is more stable than the +4 state. Consequently, Pb⁴⁺ in PbO₂ has a strong tendency to gain two electrons and get reduced to the more stable Pb²⁺ state (as found in PbO). Anything that readily gets reduced is, by definition, a strong oxidising agent.
7. What happens when you heat Lead (IV) Oxide?
When Lead (IV) Oxide is heated strongly, it undergoes thermal decomposition. It loses oxygen gas and converts to the more thermally stable Lead (II) Oxide. The chemical equation for this decomposition is: 2PbO₂(s) → 2PbO(s) + O₂(g). This reaction demonstrates the instability of the +4 oxidation state of lead at higher temperatures.
8. Is Lead (IV) Oxide toxic or dangerous to handle?
Yes, like most compounds of lead, Lead (IV) Oxide is toxic. It can be harmful if inhaled or ingested. Lead is a cumulative poison, meaning it can build up in the body over time and affect the nervous system and other organs. When working with PbO₂ in a lab setting, proper safety precautions like wearing gloves, goggles, and using a fume hood are essential.
