Ammonium Hydroxide

Let’s know about Ammonium Hydroxide. Ammonia solution , also known as ammonia water , ammonium hydroxide , ammonia alcohol , ammonia alcohol , aqua ammonia , aqueous ammonia , or (incorrectly) ammonia , is a solution of ammonia in water. It can be represented by the symbols NH 3 (aq). Although the name ammonium hydroxide suggests an alkali with the structure [NH 4 + ] [OH – ] , it is impossible to actually isolate samples of NH 4 OH. ions NH 4 + and OH -Except in extremely dilute solutions does not account for a significant fraction of the total amount of ammonia.

Ammonium Hydroxide
Ammonium Hydroxide

basicity of ammonia in water

In aqueous solution, ammonia deprotonates water to give a small fraction of ammonium and hydroxide according to the following equilibrium:

NH 3 + H 2 O NH + + OH  .

In a 1 M ammonia solution, approximately 0.42% of the ammonia is converted to ammonium equivalent to pH = 11.63 because [NH + ] = 0.0042 M, [OH  ] = 0.0042 M, [NH 3 ] = 0.9958 M, and pH = 14 + log 10 [OH  ] = 11.62. base ionization is constantb = [NH + ] [OH  ] / [NH 3 ] = 1.77 × 10 −5 .

saturated solution

Like other gases, ammonia exhibits a decreasing solubility in solvent liquids as the temperature of the solvent increases. The density decreases as the concentration of dissolved ammonia in an ammonia solution increases. At 15.6 °C (60.1 °F), the saturated solution has a density of 0.88 g/mL and contains 35.6% ammonia by mass, 308 g of ammonia per liter of solution, and has a molarity of approximately 18 mol/L. At higher temperatures, the molarity of the saturated solution decreases and the density increases. [5] Ammonia gas is released when saturated solutions are heated.


Unlike anhydrous ammonia, aqueous ammonia finds some non-niche uses outside of cleaning agents.

household cleaners

Diluted (1-3%) ammonia is also a component of many cleaning agents, including many window cleaning formulas. [6] Because aqueous ammonia is a water-soluble gas, as the water evaporates through a window, the gas also evaporates, leaving the window sills free.

In addition to being used as an ingredient in cleansers along with other cleaning ingredients, ammonia in water is also sold as a cleaning agent, commonly labeled as “ammonia.” It can be sold plain, lemon-scented (and usually yellowish), or pine-scented (green). The ammonia commonly available with soap is known as “cloudy ammonia”.

alkyl amine precursor

In industry, aqueous ammonia can be used as a precursor to some alkyl amines, although anhydrous ammonia is generally preferred. Hexamethylenetetramine is readily formed from aqueous ammonia and formaldehyde. Ethylenediamine is formed from 1,2-dichloroethane and aqueous ammonia. [7]

absorption refrigeration

In the early years of the twentieth century, the vapor absorption cycle using water-ammonia systems was popular and widely used, but after the development of the vapor compression cycle it became increasingly important due to its low coefficient of performance (about one-fifth). decreased. of the vapor compression cycle). Both the Electrolux refrigerator [8] and the Einstein refrigerator are well-known examples of this application of ammonia solutions.

water treatment

Ammonia is used to make monochloramine, which is used as a disinfectant. [9] Chloramine is preferred over chlorination for its ability to remain active for longer periods of time in clogged water pipes, reducing the risk of waterborne infections.

Ammonia is made by aquarists using an ammonia process called setting up a new fish tank for the purposes of fishless cycling. [10] This application requires that ammonia do not contain any additives.

food production

Baking ammonia (ammonium bicarbonate) was one of the original chemical leavening agents. It was obtained from deer horns. [11] It is useful as a leavening agent, as ammonium carbonate is heat activated. This characteristic allows the baker to avoid both the long proofing time of yeast and the quick wastage of baking soda in CO2 making breads and cookies rise. It is still used to make ammonia cookies and other crispy baked goods, but its popularity has waned due to concerns over the smell of ammonia and its use as a food ingredient compared to modern baking powder formulations. has decreased. It is assigned the E number E527 for use as a food additive in the European Union.

Aqueous ammonia is used as an acidity regulator to reduce acid levels in food. It is classified by the United States Food and Drug Administration as Generally Recognized as Safe (GRAS) when using the food grade version. [12] Its pH controlling abilities make it an effective antimicrobial agent.

furniture darkening

In furniture making, fuming ammonia was traditionally used to darken or stain wood containing tannic acid. After being sealed inside a container with wood, the smoke from the ammonia solution reacts with naturally occurring tannic acid and iron salts in the wood, causing the wood to darken. This technique was commonly used in furniture during the Arts and Crafts movement – ​​a furniture style that was primarily made of oak and stained using these methods. [13]

straw treatment for cattle

Ammonia solution is used to treat the straw, producing “ammoniated straw”, making it more edible for cattle.

laboratory use

Aqueous ammonia is used as a complex and base in traditional qualitative inorganic analysis. Like many amines, it gives a deep blue color with a solution of copper(II). Ammonia solution can dissolve silver oxide residues, such as that formed from Tollens’ reagent. It is often found in solutions used to clean gold, silver and platinum jewelry, but can have adverse effects on porous gemstones such as opals and pearls.

Where is ammonium hydroxide found?

Ammonium hydroxide is found naturally in the air, water and soil, and even inside humans and plants. Our own organs produce ammonia just as the beneficial bacteria in our intestines do. It also plays a role in protein synthesis. Although ammonium hydroxide is a natural compound, we also make it by diluting ammonia in water.

Is ammonium hydroxide an anion or a cation?

The chemical formula of ammonium hydroxide is NH4OH. The molar mass is 35.04 g/mol – 1. The compound structure is formed by 1 hydroxide ion (OH – ) and 1 ammonium cation NH 4 + and they share an ionic bond.