Lead (Pb), is a soft silvery-white or gray metal belonging to group 14 (IVa) of the periodic table. Lead is malleable, malleable, dense, and has poor electrical conductivity. Lead, known from antiquity and considered the oldest metal by alchemists, is very strong and corrosion-resistant, as evidenced by the continued use of lead water pipes installed by the ancient Romans. The symbol Pb for lead is an abbreviation for the Latin word plumbum, meaning lead.
The iodide ion is the I-ion. Compounds with iodine in the formal oxidation state -1 are called iodides. In everyday life, iodide is most commonly encountered as a component of salt iodide, which is mandated by many governments.
Lead Iodide
First, the formula for lead iodide or lead iodide II is salt. It is also a bright yellow, odorless, crystalline solid that turns orange and red when heated at room temperature. Previously called lead iodide. Currently, the compound has a variety of special uses, such as in the production of solar cells, and X-ray and gamma-ray detectors. However, its preparation is an interesting and popular demonstration in a wide range of chemistry education fields teaching topics such as precipitation. Decomposes in moderately high-temperature light, and we also use this effect in our proprietary photographic process. Lead iodide, formerly under the name iodide yellow, was used as a yellow pigment in many types of paints. However, this use is not currently being used due to poor toxicity and safety.
Lead Iodide Formula
The chemical formula for lead(II) iodide salt, also known as lead iodide, is PbI2. It turns orange and red when heated at ambient temperature to a bright yellow, odorless crystalline solid. Previously known as lead iodide. Another name for lead is lead. Therefore, lead iodide is also called lead iodide.
Structure of Lead Iodide
Lead iodide has a chemical formula of PbI2 and a molar mass of 461.01 g/mol. It is a simple ionic compound composed of a lead cation (Pb2+) and an iodide anion (I–). Its Chemical Structure is,
Preparation of Lead Iodide
PbI2 in an aqueous solution is usually prepared by precipitation of potassium iodide KI and lead(II) nitrate.
Pb(NO3)2 + 2 KI → PbI2 + 2 KNO3
Iodides, such as lead (II) acetate and sodium iodide, etc. are mentioned. This chemical can also be obtained by reacting iodine vapor with molten lead at temperatures between 500 and 700 degrees Celsius. PbI2 thin films can also be obtained by depositing a lead sulfide PbS thin film and exposing it to iodine vapor.
Physical Properties of Lead Iodide
- The molecular formula of lead iodide is PbI2.
- PbI2 has a molecular weight of 461.01 g/mol.
- Density (mass/volume) of lead iodide 6.16 g/dm3.
- Lead Iodide Melting Point 402°C.
- Lead Iodide Boiling Point 953°C.
- The color of iodine is yellow.
- Lead Iodide’s yellow color can only be seen in precipitated form, which disappears in the form of solutions.
Chemical Properties of Lead Iodide
- The action of Air: Lead iodide is oxidized to elemental iodine in the presence of air. The chemical equation for this oxidation reaction can be expressed as:
2Pbl2 + O2 → 2PbO + 2I2↑
- At moderate high temperatures, lead iodide decomposes under the influence of light. The decomposition products are metallic lead and gaseous iodine. This effect is used in a proprietary photographic process.
- The bright yellow lead iodide turns orange or red when heated.
- The reaction of lead iodide and sodium hydroxide: The reaction of lead iodide and sodium hydroxide produces sodium (II) trihydroxoplumbate and sodium iodide. The chemical equation can be expressed as, iodine, water, and hydrogen sulfide. The chemical equation can be expressed as,
4Pbl2 + 5H2SO4 → 4PbSO4 + 4I2 + H2S + 4H2O
Uses of Lead Iodide
- It is also used as a photon detector for X-rays and gamma rays.
- However, its use as a pigment is prohibited due to its high toxicity and low stability.
- Used for cloud seeding in aerosols.
- Used as a filter in far-infrared astronomy.
- It is also used in photosensitive recording paper, lubricants, etc.
Sample Questions
Question 1: Why is lead iodide yellow?
Answer:
Both compounds are soluble in water. When they are mixed, a double chemical substitution reaction occurs in which the lead and potassium ions switch partners to form soluble potassium iodide KCl and PbI2. It is a yellow solid that precipitates out of the solution as it is insoluble in water.
Question 2: Does lead iodide cause chemical changes?
Answer:
When a colorless solution of lead nitrate is mixed with a solution of colorless potassium iodide, a golden precipitate of lead iodide is formed.
Question 3: Is the lead iodide safe?
Answer:
Lead iodide is a potential human carcinogen. Exposure to carcinogens may not be safe, so all contact should be reduced to the lowest possible level. Sheets (MSDS) and labels to identify important safety and health information for product ingredients and product mixtures.
Question 4: Why clean with lead iodide?
Answer:
Filtration separates insoluble substances from liquids and solutions. The sediment is insoluble in water, so any remaining contaminant solution can be removed by washing with distilled water.
Question 5: How do I remove lead iodide from a test tube?
Answer:
Lead iodide can recrystallize to form larger crystals that can be removed mechanically. Pour enough water into the tube to submerge all solids. Heat gently and stop until the water boils.
Question 6: Is exist lead iodide?
Answer:
The formula for lead(II) iodide salt, also known as lead iodide, is PbI2. It turns orange and red when heated at ambient temperature to a bright yellow, odorless crystalline solid. Previously known as lead iodide. Another name for lead is lead.
Question 7: What color is lead iodide?
Answer:
Lead(II) iodide, or lead iodide, is a salt of the formula PbI2. It turns orange and red when heated to a bright yellow, odorless, crystalline solid at room temperature. It was called lead iodide.