In this lesson, you will learn about potassium bromide. We will review the basics, describe how the formula and weight are determined, and depict some of its common uses.
What Is Potassium Bromide?
Potassium bromide, under normal pressure and temperature, is a white crystalline salt (Figure 1).
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Formula and Weight
Potassium bromide is an ionic compound. It is labeled an ionic compound due to the type of bonding that occurs between the two elements – an electrostatic attraction between the two ions. One can usually predict ionic bonding based on the elements’ position on the periodic table. A metal with a non-metal will almost always have ionic bonding.
Figure 3 shows the periodic table with potassium and bromide highlighted. Potassium is a metal and bromide is a non-metal.
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Uses
Potassium bromide, especially at large concentrations, can cause nausea and vomiting if ingested. It can, however, be use used as an anticonvulsant. It is not currently used for this in the United States for humans, but it is used fairly often in veterinary medicine, typically for epilepsy in dogs. The reason potassium bromide is not approved by the FDA for humans is that it has many side effects that outweigh its successes.
It can cause skin lesions, loss of appetite, confusion with speech loss, depression, and more.Potassium bromide is also often used in the sciences for spectroscopy, especially infrared spectroscopy (IR). The compound is put under high pressure to make plates, which other substances can be placed.
Lesson Summary
Potassium bromide has the chemical formula KBr. It is an ionic salt, with a formula weight of 119 g/mol. Although potassium bromide can be used as an anticonvulsant, it is not currently used for humans because it has many deleterious side effects.