By: Paul Gilmore III
Table of Contents I. Introduction II. Properties III. Cloud Seeding
IV. Photography V. Toxicity VI. Conclusion
VII. Works Cited
Paul Gilmore III
15 April 2013
Ms. Placke
4th Period
I. Introduction
Silver Iodide is an inorganic compound represented by the formula AgI that is used in cloud seeding, photography, and can also be used as an antiseptic. These are the three main ways the compound has been used throughout the history of the world. While the compound remains to be used there have been a few concerns raised that the compound silver iodide may be toxic to humans and other organism. This paper will discuss the uses of silver iodide, whether or not the compound is toxic, and the compound itself discussing silver iodides properties. II. Properties
Silver Iodide is found as a bright yellow solid. The compound is found in three different types of structures or phases. This change in structure or phase is related to the temperature the -compound is in. The B-phase or structure is the most common of the structures this structure is most stable below 147 degrees Celsius or 420 K. The B- phase is when the chemical has a wurtzite crystal structure (Figure 1)(Silver Iodide 1) and is bright yellow. In the B-phase silver iodide is commonly known as the mineral iodargyrite (Figure 2)(Silver Iodide 1). Silver iodide also is found in the a-phase when above 420 K or 147 degrees Celsius. This structure or phase has a body-centered cubic structure. In this form the silver centers are moved randomly between 2-4 coordinate sites randomly. Also in this phase the compound silver iodide is a fast conductor of ions, because of the Ag ions moving quickly throughout the compound. The structure changes between the B and s phase because of the silver sublattice melting. There is also another phase that exist under 147 degrees Celsius or 420 K called the y-phase but it is
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