Skip to main content

Sodium iodide

ADVERTISEMENT
Identification
Molecular formula
NaI
CAS number
7681-82-5
IUPAC name
sodium;iodide
State
State

At room temperature, sodium iodide is found in a solid state. It is usually stored in airtight containers to prevent it from absorbing moisture from the air, which would lead to clumping and degradation of its crystalline structure.

Melting point (Celsius)
661.00
Melting point (Kelvin)
934.00
Boiling point (Celsius)
1 300.00
Boiling point (Kelvin)
1 573.00
General information
Molecular weight
149.89g/mol
Molar mass
149.8940g/mol
Density
3.6670g/cm3
Appearence

Sodium iodide is a white, crystalline, hygroscopic solid. It is commonly found in its anhydrous form and readily absorbs moisture from the environment. The crystals are highly soluble in water, which can give the solution a slightly reddish tint if impurities are present.

Comment on solubility

Solubility of Sodium Iodide (NaI)

Sodium iodide, with the chemical formula NaI, is known for its excellent solubility in water. This compound exhibits the following solubility characteristics:

  • Highly Soluble: Sodium iodide dissolves readily in water, making it a common choice for various applications in chemistry and medicine.
  • Temperature Dependency: The solubility of NaI increases with temperature; thus, it is more soluble in hot water compared to cold.
  • Polar Solvent: The ionic nature of NaI allows it to interact favorably with polar solvents like water, breaking down its ionic lattice and resulting in a dissolved state.

Interestingly, the solubility of sodium iodide is influenced by:

  1. Presence of Other Ions: The solubility can also be affected by other ionic species present in the solution.
  2. pH of the Solution: The pH may impact the ionization and thus influence solubility in certain scenarios.

In summary, NaI is a highly soluble compound that serves as a crucial element in various chemical processes and medicinal formulations due to its ease of dissolution. Its solubility properties reflect the fundamental principles of ionic compounds in polar solvents.

Interesting facts

Interesting Facts About Sodium Iodide

Sodium iodide, a fascinating chemical compound, is a prominent source of iodine, an essential element for human health. Here are some intriguing insights:

  • Essential for Thyroid Function: Sodium iodide plays a crucial role in the synthesis of thyroid hormones, which regulate metabolism. Iodine deficiency can lead to disorders such as goiter and hypothyroidism.
  • Uses in Medicine: In the medical field, sodium iodide is often used in diagnostic imaging. It is administered to patients undergoing thyroid scans to assess thyroid gland functionality.
  • Role in Radiation Therapy: Sodium iodide labeled with radioactive isotopes is critical in treating certain types of thyroid cancer. It selectively targets thyroid tissue, delivering radiation to destroy malignant cells.
  • Chemical Behavior: As an ionic compound, sodium iodide readily dissociates in solution, which contributes to its effectiveness as a source of iodide ions in various applications.
  • Historical Significance: The discovery of iodine by Bernard Courtois in 1811 was a pivotal moment in chemistry, leading to the identification of sodium iodide’s beneficial properties shortly thereafter.

In conclusion, sodium iodide not only serves important medical and nutritional roles but also highlights the intricate relationship between chemistry and health. As stated by chemist Linus Pauling, "The best way to have a good idea is to have a lot of ideas." Sodium iodide exemplifies how one compound can influence multiple fields, from health sciences to research.