Search databaseBooksAll DatabasesAssemblyBiocollectionsBioProjectBioSampleBioSystemsBooksClinVarConserved DomainsdbGaPdbVarGeneGenomeGEO DataSetsGEO ProfilesGTRHomoloGeneIdentical Protein internet CatalogNucleotideOMIMPMCPopSetProteinProtein ClustersProtein family ModelsPubChem BioAssayPubChem CompoundPubChem SubstancePubMedSNPSRAStructureTaxonomyToolKitToolKitAllToolKitBookgh Bookshelf. A business of the national Library that Medicine, nationwide Institutes the Health.

You are watching: If a solute dissolves in an endothermic process

StatPearls . Sweetheart Island (FL): StatPearls Publishing; 2021 Jan-.



Dissolution <1><2><3>

Dissolution is the procedure where a solute in gaseous, liquid, or solid step dissolves in a solvent to type a solution.


Solubility is the best concentration the a solute that have the right to dissolve in a solvent in ~ a provided temperature. At the best concentration that solute, the solution is stated to be saturated. The devices of solubility can be provided in mol/L or g/L.

Factors that influence solubility include: 



The price of dissolution is represented by the Noyes-Whitney equation: dm/dt = D*A*(Cs - C)/h




Effect that temperature top top liquid and solid solutes

As temperature increases, the solubility of a solid or liquid can fluctuate relying on whether the dissolved reaction is exothermic or endothermic.

Increasing solubility with enhancing temperature

In endothermic dissolution reactions, the net power from breaking and forming bonds results in heat power being took in into the system as the solute dissolves. Once the temperature the the mechanism increases, extr head energy is introduced right into the system.
So according to Le Chatelier’s Principle, the mechanism will change to this rise in the warmth by promoting the dissolution reaction come absorb the added heat energy. Raising the temperature will because of this increase the solubility the the solute.
An example of a solute whose solubility increases with greater temperature is ammonium nitrate, which deserve to be used in first-aid cold packs. Ammonium nitrate dissolve in systems is an endothermic reaction. Together the ammonium nitrate dissolves, heat power is soaked up from the atmosphere causing the surrounding setting to feeling cold.
In exothermic reactions, heat power is released once the solute dissolves in a solution. Raising temperature introduces more heat right into the system. Complying with Le Chatelier’s Principle, the device will readjust to this overabundance heat energy by inhibiting the resolution reaction. Raising temperature, therefore, decreases the solubility the the solute. 
An example of a solute that decreases in solubility with enhancing temperature is calcium hydroxide, which have the right to be offered to treat chemical burns and as one antacid.

Effect that temperature ~ above gas solutes

In general, heat power is released as gas dissolves in solution, an interpretation the dissolution reaction is exothermic. As such, a gas becomes less soluble as temperate increases.

Increasing temperature results in increased kinetic energy. Gas molecules v greater kinetic energy move more rapidly bring about the intermolecular bonds between the gas solute and also solvent breaking. 

Pressure: Henry’s law

The solubility the gas is affected by alters in press on the system. A gas disappear in liquids to type solutions. This results in equilibrium in the device where a proportion of gas molecule is dissolved in liquid while the rest continues to be in gaseous phase above the liquid.

Henry’s regulation states that: “At constant temperature, the lot of gas the dissolves in a volume of fluid is proportional come the partial press of the gas in equilibrium v the liquid.”

Henry"s regulation results in the following equation: C = kP


C to represent the solubility that the gas in ~ a certain temperature in a details solvent
K to represent Henry’s regulation constant
P represents the partial press of the gas i.e. The pressure the gas exerts top top the mechanism at a offered volume and temperature

Hence as the press of the gas over the fluid in the device increases, the gas molecule become an ext soluble in the solvent. Likewise, if the press of the gas in the mechanism decreases, gas becomes much less soluble in the solvent.

Issues of Concern

Limitations of Henry’s regulation on gas solubility:

Only applies if the gas molecules space in equilibrium
Does not apply if over there is a chemical reaction in between the solvent and the solute


Solubility <7><8><9>

Le Chatelier’s principle:

If stressors like pressure and heat are used to the equilibrium, the system will respond through adjusting to minimize the results of the stress.

For example, if push is used to a system, the resolution reaction will respond to minimize this stress and anxiety by reducing the push in the system.

Heat the solution

Solids and also liquids form as a an outcome of individual corpuscle being organized together by inter-particulate bonds. To kind a solution, power is required to break the bonds in between the particles within the heavy or liquid. Heat power is likewise required to rest the binding in a solvent to insert one of the molecules into the solution. Both that these procedures are endothermic. Heat energy is released when the solute molecules form bonds v the solvent molecule i.e. This process is exothermic.

Depending top top whether more energy is offered to break the bonds in ~ the solute and also solvent or is exit when brand-new bonds are formed between the solute and also solvent, the reaction as whole can be exothermic or endothermic.

If more energy is forced to rest the bonds in ~ the solute and solvent than is exit when brand-new bonds are formed in between the solute and solvent, the reaction is considered endothermic.
If more energy is exit when brand-new bonds space formed between the solute and solvent than is forced to rest the bonds in ~ the solute and also solvent, the reaction is considered exothermic.

The total amount of heat power released from or absorbed by the system = amount of warm energy absorbed when bond are broken – the sum of heat power released when bonds space formed

If the complete amount that heat energy released/absorbed indigenous the device is higher than zero, the reaction is endothermic.
If the complete amount the heat power released/absorbed native the device is less than zero, the reaction is exothermic.


Application of Henry’s Law: Decompression Sickness

Henry’s Law describes the phenomena that decompression sickness. As soon as scuba divers submerge us in deep water, the press of the water rises the push in their bodies. Nitrogen, a gas in our blood, disappear under the enhanced pressure. Nitrogen is physiologically inert, so the is not used in tissue metabolism. If the scuba diver ascends to the surface ar too quickly, the rapid fall in pressure decreases the solubility of nitrogen, causing nitrogen bubbles to come out of solution. The nitrogen balloon can type painful and also potentially deadly gas embolisms.

Clinical Significance


Dissolution is necessary for health practitioners because, because that drugs to be took in and have actually a physiological effect in the person body, they need to be in solution. Because that solid preparations, such together tablets and suppositories, the rate of dissolution affects how rapid a drug is took in in the body.


Aqueous solubility is often thought about when formulating drugs. Poorly dissolve formulations provide difficulties in the development of pharmaceuticals. Chloramphenicol, phenytoin, and digoxin are some examples. Drugs, specifically those for dental administration, may have poor aqueous solubility. This may result in short bioavailability top to insufficient exposure and physiologic impact in the body.

Review Questions


Joshi K, Chandra A, Jain K, Talegaonkar S. Nanocrystalization: one Emerging technology to boost the Bioavailability the Poorly dissolve Drugs. Pharm Nanotechnol. 2019;7(4):259-278.
Itai S. . Yakugaku Zasshi. 2019;139(3):419-435.
Karaźniewicz-Łada M, Bąba K, Dolatowski F, Dobrowolska A, Rakicka M. The polymorphism that statins and also its impact on their physicochemical properties. Polim Med. 2018 Jul-Dec;48(2):77-82.
Sujka M, Pankiewicz U, Kowalski R, Nowosad K, Noszczyk-Nowak A. Porous starch and its application in drug distribution systems. Polim Med. 2018 Jan-Jun;48(1):25-29.
Modica de Mohac L, Keating AV, de Fátima Pina M, Raimi-Abraham BT. Engineering of Nanofibrous Amorphous and Crystalline hard Dispersions for dental Drug Delivery. Pharmaceutics. 2018 Dec 24;11(1)
Couillaud BM, Espeau P, Mignet N, Corvis Y. State of the arts of medicine Solid Forms: from decision Property worries to Nanocrystals Formulation. ChemMedChem. 2019 january 08;14(1):8-23.
Ribeiro ACF, Esteso MA. Move Properties for Pharmaceutical Controlled-Release Systems: A short Review of the prestige of Their research in organic Systems. Biomolecules. 2018 Dec 17;8(4)

See more: 3/4 Inch Pine, What Size Round Over Bit For 3/4 Wood Working

Radivojev S, Zellnitz S, Paudel A, Fröhlich E. Searching for physiologically appropriate in vitro dissolution approaches for orally inhaled drugs. Int J Pharm. 2019 Feb 10;556:45-56.
Kadokawa JI. Dissolution, derivatization, and functionalization of chitin in ionic liquid. Int J Biol Macromol. 2019 Feb 15;123:732-737.