Facts about Aqua regia.

 Facts about Aqua regia







        The name "Aqua regia" is a latin word, which means "royal water" or "regal water". Its name is "Aqua regia" because royal metals of the periodic table, such as gold and platinum, can dissolve in it. Aqua regia can dissolve noble metals such as gold and platinum, but it can't dissolve tantalum, iridium, and some other metals.



Pic of aqua regia solution
(Aqua regia solution in a beaker)



        Aqua regia is a very strong acid. It is a chemical composition of nitric acid (HNO3) and hydrochloric acid (HCl) in a 1:3 molar ratio.


About the Father of Aqua regia :-


        Aqua Regia was discovered by "Abu Musa Jabir ibn Hayyan" (also known as "Jabir ibn Hayyan" and "Gaber"). He was a Persian alchemist. (He is also known as the father of chemistry). Geber was discovered aqua regia around the year 800AD, when he mixed common salt (NaCl) with vitriol [ Sulfuric acid (H2SO4) was known as "vitriol" in encient times ]. This was the way that the alchemist tried to find aqua regia at that time.


Formation and Decomposition of Aqua regia :-


        The chemical reaction of concentrated HNO3 and HCl gives water and volatile products such as nitrosyl chloride (NOCl) and chlorine gas. So that the aqua regia appears smoky and yellow color.


HNO3(aq) + 3 HCl(aq) ➝ HOCl(g) + Cl2(g) + 2 H2O(l)

        When volatile products escape from aqua regia, it loses its energy and nitrosyl chloride (NOCl) decomposes into nitric oxide & chlorine gas.

2 NOCl (g) ➝ 2 NO(g) + Cl2(g)

        The smoke over the aqua regia is a combination of chlorine gas and nitrogen dioxide gas. Here nitrogen dioxide gas is produced from nitric oxide. After nitric oxide is formed, it reacts with atmospheric oxygen to give nitrogen dioxide.

2 NO(g) + O2(g) ➝ 2 NO2(g)


Reaction of Aqua regia :-

(1) Dissolving of Gold :-

        When we add gold to an aqua regia solution, it gives chloroauric acid, nitrogen dioxide (or, nitric oxide), hydronium ion and water.

Au(s) + 3 HNO3(aq) + 4 HCl(aq) ⇌ [AuCl4]¯(aq) + 3 NO2(g) + [H3O]^+(aq) + 2 H2O(l)

Or,

Au(s) + HNO3(aq) + 4 HCl(aq) ⇌ [AuCl4]¯(aq) + NO(g) + [H3O]^+(aq) + H2O(l)

This is how gold dissolves in aqua regia solution.


(2) Dissolving of Platinum :-

        Platinum also reacts with aqua regia. When platinum reacts with aqua regia it gives chloroplatinous acid (H2PtCl4), nitrosoplatinic chloride ((NO)2PtCl4) & water.

2 Pt(s) + 2 HNO3(aq) + 8 HCl(aq) ➝ (NO)2PtCl4(s) + H2PtCl4(aq) + H2O(l)

        Again, (NO)2PtCl4 reacts with HCl and gives chloroplatinous acid & nitrosyl chloride.

(NO)2PtCl4(s) + 2 HCl(aq) ⇌ H2PtCl4(aq) + 2 NOCl(g)

        Chloroplatinous acid can again be oxidised to chloroplatinic acid (H2PtCl6), when it is heated with chlorine gas.

H2PtCl4(aq) + Cl2(g) ➝ H2PtCl6(aq)

This is the process in which platinum dissolves into aqua regia.


(3) Reaction with Tin :-

        Aqua regia also reacts with tin to give tin(IV)chloride, nitrogen dioxide, nitric oxide & water.

Sn + 4 HCl + 2 HNO3 ➝ SnCl4 + NO2 + NO + 3 H2O


(4) Reaction with Iron pyrite (FeS2) :-

        When aqua regia reacts with iron pyrite, it gives nitric oxide, sulphuric acid, ferric chloride and water.

FeS2 + 5 HNO3 + 3 HCl ➝ FeCl3 + 2 H2SO4 + 5 NO + 2 H2O



Some Other Information About Aqua regia :-



Chemical formula of Aqua regia
(Chemical formula of Aqua regia)

    
        The chemical formula of aqua regia is HNO3 + 3 HCl. It looks as a red, orange or yellow fuming liquid. Its melting point and boiling point are 231K and 381K respectively. The IUPAC name of aqua regia is nitric acid hydrochloride. It is also known as nitrohydrochloric acid and royal water.



Use of Aqua regia (Application) :-


        Aqua regia is mainly used in the extraction and purification of gold and platinum (it gives 99.99% of pure gold and platinum). It is also used in metal etching and analytical processes.







Click here ⤵️

Comments

Post a Comment

Popular Posts By Scientific facts... :—

Baseball plant facts.

Image
  Baseball plant facts. (Baseball plant) Common name :-      Baseball plant Kingdom :-                 Plantae Order :-                       Malpighiales Family :-                     Euphorbiaceae Genus :-                      Euphorbia Species :-                    obesa Scientific name :-      Euphorbia obesa Appearance :-           Spherical The baseball plant is scientifically known as Euphorbia obesa. It is a succulent flowering plant and its pod contains about two to three seeds in it. It is a slow growing wild plant. Due to its over collection, this plant is in a danger condition. It is cultivated in normal gardens and botanical gardens, because of its unique appearance, and to study about this plant. It is seen in subtropical regions and is native to Cape Province, South Africa.         A baseball plant looks exactly like a ball, therefore, this plant is called so. It is about 6 c.m to 15 c.m in diameter and the young plants look spherical but they get cylindrical shape accor
Read more

Interesting Facts About The Superb-bird-of-paradise (Lophorina superba).

Image
  Facts About An Interesting And Beautiful Bird Superb-bird-of-paradise. (Picture of Superb-bird-of-paradise)  Kingdom :-                  Animalia Phylum :-                    Chordata Class :-                         Aves Order :-                        Passeriformes Family :-                      Paradisaeidae Genus :-                        Lophorina Species :-                      superba Scientific name :-      Lophorina superba Diet :-                          Omnivore Lifespan :-                 5–8 years About The Superb-bird-of-paradise   :-                The superb-bird-of-paradise is also known as "Greater lophorina" and "Greater superb-bird-of-paradise". Its scientific name is " Lophorina superba ". These birds are seen in Indonesia and Papua New Guinea. These are very rare types of birds and it was considered that they are only one species in their genus but in 2017 their two new species were found. The other two species are " Lophorina
Read more

Comparison between Light & Sound | Similarity and Difference between Light and Sound.

Image
Similarity and Difference between Light and Sound.   (Light and Sound Waves) Similarity :-  (1)👉  Both light and sound are forms of energy. (2)👉 They both have wave nature. (3)👉 Both light and sound have properties of wavelength, frequency and amplitude. (4)👉 The reflection laws of light and sound are same. i.e.–           (I) The angle of reflection is equal to the angle of incidence.          (II) The reflected sound ( reflected ray for light), the incident sound (incident ray for light) and the normal belong in the same plane. (Here i= Angle of incident sound wave and r= Angle of reflection) (Reflection of Sound) (Here 𝞱 i = Angle of incident ray and 𝞱 r  =Angle of reflection) (Reflection of Light) Difference :- (1)👉 The most common difference between light and sound is that we can see light and we can hear sound. (2)👉 Both are energy but sound is a mechanical energy and light is a electromagnetic energy. (3)👉 Sound has only wave property but light has both wave & par
Read more

Umbonia spinosa Facts | A Beautiful Insect Bug Espino.

Image
Beautiful insect Umbonia spinosa     (Pics of Bug Espino)                   Umbonia spinosa is a scientific name of bug Espino. It is a beautiful & attractive insect. It is some time called as a Thorn bug, because its horn resembles a thorn. It is famous for its appearance of dorsal horn. Dorsal side colour of bug espino is yellow, blue or light green, with each side of red, black or yellow vittae.                   They have 6 legs like other insects. They are herbivorous and eat the plants on which they live. These are seen in Central and South America, Mexico, Florida and Asia. Kingdom :-        Animalia Phylum :-          thropoda Class :-              Insecta Family :-            Membracidae Genus :-            Umbonia Species / Scientific name :-  Umbonia spinosa Diet :-                Herbivore Click here ⤵️ Visit Our Home and Read More Articles⇒🏠
Read more