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Ammonium Iodide Formula - Structure, Chemical Formula and Properties

The Ammonium Iodide Formula is NH4I. Ammonium Iodide Formula consists of one ammonium cation (NH4+) and one iodide anion (I)-. It is an ionic compound formed through the combination of these ions.
authorImageSawat Sayyed20 Oct, 2023
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Ammonium Iodide Formula

The ammonium iodide formula is NH4I and has multiple uses in photographic chemicals and medications. Ammonium Iodide Formula preparation involves combining hydroiodic acid with ammonia. It readily dissolves and forms cubic crystals when mixed with water (H2O). Additionally, it can be dissolved in ethanol solution and will turn yellow upon exposure to moist air due to decomposition and release of iodine.

Ammonium Iodide Formula

Ammonium iodide is a chemical compound with the formula NH4I. This formula represents the composition of the compound, showing that it consists of one ammonium cation [(NH4)+] and one iodide anion [(I)-].

Ammonium Iodide Formula

Also Read: Cyanide Formula

Ammonium Iodide Formula - Ionic Compound

Ammonium iodide is an ionic compound. It is formed through the combination of an ammonium cation (a positively charged ion) and an iodide anion (a negatively charged ion). The electrostatic attraction between these oppositely charged ions holds the compound together.

Ammonium Iodide Formula

Also Read: Butyric Acid Formula

Ammonium Iodide Formula by the Crisscross Method

The crisscross method can be used to determine the formula of ammonium iodide. Ammonium has a charge of +1, and iodide has a charge of -1. You simply need one ammonium cation for one iodide anion to balance the charges, resulting in the formula NH4I.

Ammonium Iodate Formula

Ammonium iodide should not be confused with ammonium iodate, which has a different chemical formula. The formula for ammonium iodate is (NH4)2IO3, indicating that it contains two ammonium cations and one iodate anion.

Ammonium Iodate Formula

Ammonium Iodide Formula - Ionic or Covalent

Ammonium iodide is an ionic compound, as it is composed of ions with opposite charges. The ammonium ion [(NH4)+] is formed through a covalent bond within the ion, but when combined with the iodide anion [(I)-], it forms an ionic bond.

Also Read :

Ammonium Iodide Chemical Formula

The chemical formula of ammonium iodide is NH4I. This compound is commonly used in various chemical applications, including as a source of iodine in chemical reactions or for photographic purposes. It is a white crystalline salt that is soluble in water.

Also Read: Carbonous Acid Formula

Preparation of Ammonium Iodide

Our first step is to dissolve 254 grams of potassium iodide in 125 milliliters of water (H2O) and mix it with 100 milliliters of ammonium sulfate. Then we have to dissolve it in boiling water. Once it has cooled down, we add 40 milliliters of alcohol to it and keep it for 12 hours.

As a result, we obtain a precipitate of potassium sulfate that we filter, then we evaporate the filtrate occasionally by adding ammonia water with a small amount of alcohol until crystallization occurs. In addition, we wash the potassium sulfate crystals with dilute alcohol, which contains about 20% alcohol. Furthermore, after combining the filtrates and evaporating, we obtain ammonium iodide.

The equation is (NH4)2SO4 + 2KI →2NH4I + K2SO4

As ammonium iodide crystallizes into cubes and deliquesces in the air, it must be preserved in a dark place because the light decomposes the salt, causing it to turn brown.

To crystallize, the solution is treated with ammonium sulfide, filtered, and evaporated with a steam bath. The aqueous solution is readily soluble in alcohol. As a result of the decomposition and separation of the iodine, the solution turns yellow when standing for some time. One part of the salt dissolves in 0.60 parts of water (H2O).

Ammonium iodide can also be made in a laboratory by reacting ammonia or ammonium hydroxide with hydroiodic acid or hydrogen iodide:

A combination of NH3+HI → NH4I

It is calculated by multiplying NH4OH + HI → NH4I + H2O.

Also Read: Cholesterol Formula

Properties of Ammonium Iodide

Besides being visible as a white crystalline powder, ammonium iodide has a melting point of 551 °C and a boiling point of 405 °C, a molar mass of 144.94 g/mol, a density of 2.51 g/cm3, and is easily soluble when put into water (H2O).

Properties of Ammonium Iodide
Name Ammonium Iodide
Appearance White crystalline powder
Chemical Formula NH 4 I
Melting Point 551 °C
Boiling Point 235 °C
Molar Mass 144.94 g/mol
Density 2.51 g/cm³
Solubility in Water Soluble
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Ammonium Iodide Formula FAQs

How do you write ammonium iodide?

Ammonium iodide is written as NH4I, representing its chemical formula. This formula consists of one ammonium cation [(NH4)+] and one iodide anion [(I)-].

What is the chemical name for ammonium iodide?

The chemical name for ammonium iodide is "ammonium iodide." It is also commonly referred to by this name.

Is ammonium iodide a salt?

Yes, ammonium iodide is a salt. It is formed by the combination of an ammonium cation and an iodide anion, resulting in an ionic compound. Salts are compounds composed of cations and anions held together by ionic bonds, and ammonium iodide fits this description.

What is the formation of ammonium iodide?

Ammonium iodide is formed through a chemical reaction between ammonia (NH3) and hydroiodic acid (HI). The reaction can be represented as follows: NH3 + HI → NH4I In this reaction, ammonia reacts with hydroiodic acid to produce ammonium iodide (NH4I), which is a white crystalline salt.
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