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Potassium Bromide

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KBr: Potassium Bromide

In this content, you will find all important information about potassium bromide uses, its properties, and production. Potassium bromide is a chemical compound of the element potassium or K and bromine or Br2. At room temperature, potassium reacts with bromine, and by synthesis, this compound is formed. The chemical equation of this reaction is 🡪 2 K + Br2 = 2KBr. 


Potassium bromide has an immense contribution to medical science. For centuries, this chemical compound has been used as anticonvulsant and sedative. The following discussion is an in-depth discussion about KBr.


What is Potassium Bromide?

Now, the first question that can arise in your mind is “what is potassium bromide”. Thus, here is the answer-


KBr or Potassium bromide is an ionic salt, completely disassociated, and has a value of pH 7 in an aqueous solution. It is also known as Kalii bromidum, Tripotassium tribromide, and bromide salt of potassium. This salt can appear as colorless crystals, crystalline powder in white or white grains under standard temperature and pressure. Taste-wise, potassium bromide is pungent bitter with saline flavor. However, this bromide salt tastes sweet in dilute aqueous solutions.


However, if you can increase the concentrations gradually, KBr tastes bitter and eventually becomes salty. This concentration-wise change of taste occurs because of the characteristics of potassium ions. Notably, potassium bromide can irritate the mucous membrane of the gastric if consumed in high concentrations. Sometimes this may cause vomiting as a general effect of every potassium salt.


This compound is completely water-soluble. This means, when put into water, it can be quickly disassociated into individual ions and disappear. 


Structure of Potassium Bromide

Its structure is created by a single cation K+ and a single anion Br-. The crystalline structure of this salt is precisely octahedral. This structure is formed by one potassium cation surrounded by six bromine anions and also vice versa. For common representation, the chemical structure of potassium bromide can be expressed as below-


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Moreover, to understand the electron representations in the valence shell, you need to learn the Lewis structure. By this electron-dot diagram, you can understand the electron arrangement of individual atoms in a molecule. Also, this diagram can help you to understand how a single pair of electrons can exist inside a molecule. 


This way, it will be easy to understand the reaction between potassium cation and bromine anion, here is the Lewis dot structure of KBr-


(Image will be uploaded soon)


Till now, you learned some common characteristics of this ionic salt. Now, let us move forward to know the other properties of potassium bromide.


  • Physical Properties

For your convenience, here are some physical properties of this salt in a nutshell-


Properties of Potassium Bromide


Properties

Details 

The chemical formula of potassium bromide

KBr

The molar mass of potassium bromide

119.002 gram/mol

Density of KBr

2.74 gram/cm3

Appearance in standard condition

White solid

Structure

Cubic

Occurrence

It does not present in nature

Taste

Bitter, Salty, Pungent, Strong

Odour

Odourless 

Soluble in 

Water, Glycerol, Ethanol

Solubility in water

535 g/L in 0oC, 678 g/L in 25oC, and 1020 g/L in 100oC

Solubility in glycerol

217 g/L

Solubility in ethanol

47.6 g/L in 80oC

Meting point

734oC

Boiling point

1435oC


  • Chemical Properties

Potassium Bromide Reactions: It is a typical ionic salt that is completely dissociated in an aqueous solution at a pH of around 7. In the production of silver bromide for photographic films, this reaction is crucial. The following is the reaction:


KBr(aq) + AgNO3(aq) → AgBr(s) + KNO3(aq)


When bromide reacts with metal halides like copper (II) bromide in its aqueous state, it forms complexes:


2 KBr(aq) + CuBr2(aq) → K2[CuBr4](aq)


Quiz

  1. What Kind of Bonding Do You Find In Potassium Bromide?

Options:

  1. Covalent

  2. Metallic

  3. Ionic

  4. None of the above


  1. What Is The Charge of Bromine Ion and Potassium ion, Respectively?

Options:

  1. +1, -1

  2. -1, +1

  3. 0, 0

  4. -2, -1


  1. How Can You Reduce The Halide Anion From a Solution?

Options:

  1. By adding silver ion

  2. By adding bromine ion

  3. By adding potassium ion

  4. None of the above


  1. What Type of Electrolyte Is Potassium Bromide?

Options:

  1. Weak

  2. Not an electrolyte

  3. Strong

  4. None of these options


  1. How Can Bromine Be Separated from Potassium Bromide Solution?

Options:

  1. Chlorine water

  2. Potassium iodide

  3. Iodine solution

  4. Sodium chloride


Answers

  1. Potassium bromide has ionic bonding between its two elements potassium and bromine.

  2. Bromine has a -1 charge, and potassium has a +1 charge.

  3. Silver ions can dissolve halide anions out.

  4. Potassium bromide is a strong electrolyte as it can be entirely dissociated in an aqueous solution.

  5. As chlorine is considered the stronger oxidizing substrate than bromine, it can react with potassium bromide and generate KCl and bromine gas. Here is the chemical equation of this reaction-


2 KBr + Cl2 🡪 2 KCl + Br2 


Uses of Potassium Bromide

The next important question which arises is “what is potassium bromide used for”. Thus, the following are some crucial usages of KBr.

  • During the 19th or 20th century, this compound was utilized as a medicine against convulsions. However, nowadays, it is majorly used as an antiepileptic medicine for veterinary uses. 

  • One of the most vital usages is as sedatives.

  • Commonly, this is also operated in the infrared spectroscopy technique. This utilization is majorly performed because of its transparent crystal formation with zero optical absorption.

  • In the photographic plates and paper manufacturing industry, it is one of the most widespread chemical compounds.

  • As a heat stabilizer in nylon production, potassium bromide is regarded as a popular chemical agent.

  • It is also used to treat aquariums.

  • This is also a popular plasticiser.

  • Some other potassium bromide used are as laboratory agents and manufacture chemicals.


Application of Potassium Bromide in Veterinary Medicine

Before the introduction of phenobarbital, potassium bromide was licensed to treat several seizure disorders in humans. Nonetheless, it is still regarded as an antiepileptic drug for animals. It works at the cellular level to reduce seizure activities by suppressing neuronal excitability and activity. Potassium bromide can be taken orally and is mostly excreted by the kidneys.


However, it is hardly considered under first-line drugs as it acts slowly and takes nearly four months to achieve a stable concentration of bromide ions inside the brain. Moreover, it is always prescribed along with phenobarbital in initial stages. However, depending on the species of animal, the dose or usages can be different. 


For example, cats are prone to potassium bromide side-effects. Thus, they are mostly treated with this compound. However, dogs can be treated with potassium bromide as per medical practitioner advice. 


Some common side-effects of potassium bromide found in animals are lethargy, vomiting, transient sedation, pancreatitis, polydipsia, anorexia, constipation, and polyuria.


Precautions

  • The level of bromide ion can be affected by chloride as these two ions compete to take up the cellular membrane. 

  • Low-salt or low-sodium diets can increase bromide toxicity in animals. Contrarily, a high sodium diet can decrease the bromine level and increase the risk of seizure. 

  • In dogs, the reproductive safety of Br is yet to be proved. However, in humans, Br can go through the placenta and also is present in lactation.

  • Older animals can experience intense adverse side effects.


How are Bromides Given

Bromides are taken by mouth as a chewable pill or liquid solution, and should be taken with meals to reduce stomach distress. It can either be incorporated with food or given straight by mouth with a meal as long as the complete dose is consumed. Elevate the food dish if it has been blended into the food. To avoid discomfort in the mouth or throat, ensure the capsule is thoroughly taken and followed by food or drink. With a precise measuring device/syringe, carefully measure liquid dosages. If gastrointestinal distress persists after taking the medication with food, divide the one daily dose into several doses spread out over a 24-hour period. Salty meals should not be given. If your veterinarian advises, do not abruptly cease using this medicine. It may take a few weeks for the full effects of this drug to become apparent, although incremental improvements are normally seen. Side effects might happen right away.


Potassium Bromide Drug Information and Indication

Potassium bromide is an antiepileptic medication used in dogs to treat seizures that cannot be controlled by phenobarbital alone or in dogs that do not handle phenobarbital well. Potassium bromide reduces seizure activity in the central nervous system. Because of the high prevalence of adverse effects, cats are less likely to be treated with potassium bromide. Although potassium bromide is an efficient medication, it might take up to four months for the concentration to reach effective levels. Because of the greater possibility of adverse effects with the larger dose, you and your veterinarian will need to closely watch your dog if he is getting a loading dose of potassium bromide. The level of the antiepileptic medicine in your dog's blood will need to be measured on a frequent basis. Your veterinarian will create a suitable dosage for your dog based on this information. Your dog will very certainly be treated for the rest of their life.


Safety Hazards

Besides being used as medicine, it has some significant side effects as well. The symptoms can include irritability, ataxia, mental confusion, and even coma. In some cases, this chemical compound can cause skin rashes, hallucination, mania, and drowsiness. Potassium bromide in large quantities causes sensory disturbances, vertigo, death, and increases the pressure of the spinal fluid.


Furthermore, the potassium salt is a major irritant to the eyes. If swallowed in heavy quantity, this substate causes delirium, psychosis, and somnolence.


Hopefully, from the above content, you have understood the chemical compound potassium bromide- KBr, its structure, and its properties. If you need more references on potassium bromide uses and applications, you can visit our Vedantu website now. You can also download our Vedantu app for better access.

FAQs on Potassium Bromide

1. Can I find relevant study materials for Chemistry on Vedantu?

On Vedantu's website, students will be able to download any Chemistry chapter or topic. The concepts are well discussed, with specific examples that students may use to practise and gain confidence. It is also assured that the content supplied by our staff adheres to the curriculums provided by the different boards as well as the suggested literature. As a consequence, students do not need to be concerned that the study material is proper and written in accordance with the standards of each board. Students can also use a smartphone app to access Vedantu's online learning services, which can be downloaded for free. Vedantu's online learning offerings are accessible via a free mobile app. Vedantu's mobile app was created to provide students with the assistance and comfort they require when studying, as books and computers cannot be transported everywhere. The mobile programme may be downloaded at any time, giving students the opportunity to study or review anytime they have free time.

2. What are the potassium bromide uses?

Potassium bromide, the ionic potassium salt is mostly used as a sedative and anticonvulsant drug to control seizures.

3. What is the working process of potassium bromide?

Chloride and bromide ions fight to enter brain tissue. If the bromine level becomes greater than chlorine, the electrical activity inside the nervous system is distorted, and the chances of a seizure become difficult.

4. What happens when KBr is dissolved in the water?

When KBr is dissolved in water, it breaks into K+ or potassium ions and Br- or bromine ions.

5. What kinds of safety hazards are associated with KBr?

Irritability, mental confusion, ataxia and even coma can be the side-effects of KBr.