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Properties of Potassium permanganate (KMnO 4 ) 1. Potassium permanganate (KMnO 4 ): Action of Heat Potassium permangante on strong heating gives potassium manganate, manganese dioxide and oxygen. 2 KMnO 4 ----------> K 2 MnO 4 + MnO 2 + O 2 2. Oxidising properties of Potassium permanganate (KMnO 4 ) Potassium permanganate is a powerful oxidizing agent in alkaline or acidic solution. The relevant half reactions are: 1. Alkaline medium (pH > 7) MnO 4 - + 2H 2 O + 3 e - ----------> MnO 2 + 4OH - 2. Acidic medium (pH <7) MnO 4 - + 8H + + 5e - ----------> Mn 2+ + 4H 2 O A few important oxidizing reactions of Potassium permanganate ( KMnO 4 ) 1. In acidic medium potassium permanganate oxidizes green ferrous salts to yellow ferric salts MnO 4 - + 8H + + 5Fe 2+ ----------> 5Fe 3+ + Mn 2+ + 4H 2 O 2. in acidic medium potassium permanganate oxidizes oxalic acid or oxalate salts to CO 2 and water 2 MnO 4 - + 16H + + 5 C 2 O ...

Pottassium Permanganate ( KMnO 4 ) is prepared from Pyrolusite ore ( MnO 2 ). The finely powdered Pyrolusite ore ( MnO 2 ) is fused with an alkali metal hydroxide like KOH in the presence of air or an oxidizing agent like KNO 3 to give the dark green potassium Manganate ( K 2 MnO 4 ). Potassium manganate disproportionate in a neutral or acidic solution to give potassium permanganate . 2 MnO 2 + 4 KOH + O 2 ----------> 2K 2 MnO 4 + 2H 2 O 3 MnO 4 2- + 4H + ------------> 2MnO 4 - + MnO 2 + 2H 2 O Commercially potassium permanganate is prepared by the alkaline oxidative fusion of Pyrolusite ore ( MnO 2 ) followed by the electrolytic oxidation of manganate (4) ion . 2 MnO 2 + 4KOH + O 2 -----------> 2 K 2 MnO 4 + 2H 2 O MnO 4 2- ------( electrolytic oxidation )----> MnO 4 - + e - Properties Potassium permanganate forms dark purple (almost black) crystals , which are iso structural with those of KCLO 4 . It has weak temperature dependent...

Preparation of Potassium dichromate ( K 2 Cr 2 O 7 ) Potassium dichromate (K 2 Cr 2 O 7 ) is prepared from chromite ore FeCr 2 O 4 . The chromite ore is fused with sodium or potassium carbonate in free access of air. 4FeCr 2 O 4 + 8Na 2 CO 3 + 7O 2 -------> 8Na 2 CrO 4 + 2FeO 3 + 8CO 2 The yellow solution of sodium chromate is filtered and acidified with sulfuric acid to give a solution from which orange sodium dichromate , Na2Cr2O7 2H2O can be crystallized. 2Na 2 CrO 4 + 2H + ---------> Na 2 Cr 2 O 7 + 2Na + + H 2 O Sodium dichromate is more soluble than potassium dichromate. Hence sodium dichromate when fused with KCl forms orange crystals of potassium dichromate. Na 2 Cr 2 O 7 + 2KCl --------> K 2 Cr 2 O 7 + 2NaCl The chromates and dichromates can be inter convertible. 2CrO 4 2- + 2H 2+ ---------> Cr 2 O 7 2- + H 2 O Cr 2 O 7 2- + 2OH- ---------> 2CrO 4 2- + H 2 O The dichromate ion and chromate ion exist in equilibrium with each other at a pH of ...

Uranium is the last element occurring in nature. The elements coming after uranium are called transuranium elements. They are all synthetic in nature and are man made. They are radioactive and most of them have short half lives. For example :- 238 U 92 + 1 n 0 → 239 U 92 → 239 Np 93 + 0 e -1 Uranium → Neptunium 239 Np 93 → 239 Pu 94 + 0 e -1 Neptunium → Plutonium ( Here the Uranium(238,92) is abundant and non fissionable, It can be made into fissionable by reaction given above ) The element beyond actinides in the periodic table form atomic number 104 to 112 are called transactinide elements. These elements are rutherfordium (Rf), dubnium (Db), Seaborgium (Sg) etc. The nuclear reactions for the preparation of some of the transactinide elements are given below. 249 Cf 98 + 12 C 6 → 257 Rf 104 + 4 1 n 0 Californium → Rutherfordium 249 Cf 98 + 15 N 7 → 257 Db 104 + 4 1 n 0 Californium → Dubinium For more detail visit Indiastudychannel .com

Mercury forms halides in the two oxidation states, +1 and +2. 1. Mercury(1)Chloride(Hg2Cl2) Mercury(1) chloride or mercurous chloride is known as calomel. Preparation Mercury(1)chloride is prepared by heating a mixture of mecury(2)chloride and mercury in iron vessel. HgCl2 + Hg -------> Hg2Cl2 It can also be obtained by reduction of mercury(2)chloride by reducing agents like tin(2)chloride in limited quantity. 2HgCl2 + SnCl2 --------> HgCl2 + SnCl4 Properties When heated, mercury(1)chloride decomposes into mercury(2)chloride and mercury. Hg2Cl2 -------> HgCl2 + Hg The action of aqueous ammonia on the solid mercury(1)chloride gives a mixture of black finely divided mercury and white mercury amino chloride. This reaction is an example of disproportion reaction. Hg2Cl2 + 2Nh3 -------> Hg(NH2)Cl + Hg + NH4Cl Uses of mercury(1)chloride Calomel is used in making standard calomel electrodes used as secondary reference electrode. It is also used as a purgative in medicines. 2. Merc...

Preparation Silver nitrate is prepared by dissolving silver in dilute nitric acid. 3Ag + 4HNO3 ------> 3AgNO3 + 2H2O + NO Properties Silver nitrate on heating decomposes to form silver, nitrogen dioxide and oxygen. 2AgNO3 ---------> 2AgNO2 + O2 AgNO2 ---------> Ag + NO2 Silver nitrate is also decomposed by organic matter, such as glucose, paper, skin and cork. It has also a caustic and destructive effect on organic tissues. Uses of silver nitrate Large quantities of silver nitrate are used in the production of light sensitive plates, film and papers. In the laboratory it is used as a reagent for the detection of halide ions. It is used in making inks and hair dyes. In small doses, silver nitrate is used as a medicine for nervous diseases. Silver halides Silver fluorides may be prepared by the action of hydrofluoric acid on silver(1) oxide. Ag2O + 2HF -------> 2AgF + H2O Silver chloride, silver bromide and silver iodide are prepared by the action of silver nitrate on sodium ...

Copper sulphate penta hydrate is known as blue vitirol and is the most common oxosalt of copper(2) Preparation Copper sulphate is prepared industrially by blowing a current of air through copper scrap and dilute sulphuric acid. 2Cu + 2H2O + O2 --------> 2CuSO4 + 2H2O The crude copper(2) sulphate solution obtained contain iron(2) sulphates as impurity Dilute nitric acid is added to oxidize iron(2) to iron(3) sulphate which remains in solution after crystallization and CuSO4 5H2O crystallizes out. The crystalline copper(2) sulphate, CuSO4 5H2O has the structure in which four water molecules are coordinated to the central copper cation in square planar structure. The fifth water molecule is held by hydrogen bonds between a sulphate anion and a coordinated water molecule. The fifth hydrogen bonded water molecule is deeply embedded in the crystal lattice and hence not easily removed. Properties 1. Copper sulphate penta hydrate is a blue coloured crystalline solid, soluble in water. 2. Ac...