ANALISIS PERMANGANOMETRIANALISIS PE

ANALISIS PERMANGANOMETRI
ANALISIS PERMANGANOMETRI








PENGERTIAN
Permanganometri adalah metode titrasi redoks dengan pereaksi MnO4- (ion permanganat). Kalium permanganat merupakan oksidator yang dapat bereaksi dengan cara yang berbeda- beda, tergantung dari pH larutannya. Kekuatannya sebagai oksidator yang berbeda- beda sesuai dengan reaksi yang terjadi pada pH yang berbeda itu. Reaksi yang bermacam ragam ini disebabkan oleh keanekaragaman valensi Mn, dari 1 sampai dengan 7 yang semuanya stabil kecuali valensi 1 dan 5. Reduksi MnO4- berlangsung sebagai berikut:
1. Dalam suasana asam [H+], 0,1N atau lebih.
MnO4- + 8H+ + 5e- à Mn2+ + 4H2O.........................................(1)
2. Dalam suasana netral, pH 4-10
MnO4- + 4H+ + 3e- à MnO2 + 2H2O................................................(2)
3. Dalam suasana basa [OH-] 0,1N atau lebih
MnO4- + e- à MnO42-
Kebanyakan titrasi dilakukan dalam keadaan asam menurut (1), disamping itu ada beberapa titrasi yang sangat penting dalam suasana basa untuk bahan- bahan organik. Daya oksidasi MnO4- dalam keadaan ini lebih kecil sehingga letak keseimbangan kurang menguntungkan. Untuk menarik keseimbangan kearah hasil titrasi, titrat ditambah Ba2+yang dapat mengendapkan MnO42- menjadi BaMnO4. Selain menggeser keseimbangan kearah kanan, pengendapan ini juga mencegah reduksi MnO4- itu lebih lanjut. (Harjadi, 1993)
Pada permanganometri, titran yang digunakan adalah kalium permanganat. Kalium permanganat mudah diperoleh dan tidak memerlukan indikator kecuali digunakan larutan yang sangat encer serta telah digunakan secara luas sebagai pereaksi oksidasi selama seratus tahun lebih. Setetes permanganat memberikan suatu warna merah muda yang jelas kepada volume larutan dalam suatu titrasi. Warna ini digunakan untuk menunjukkan kelebihan pereaksi.

Kalium Permanganat distandarisasikan dengan menggunakan natrium oksalat atau sebagai arsen (III) oksida standar-standar primer. Reaksi yang terjadi pada proses pembakuan kalium permanganat menggunakan natrium oksalat adalah:
5C2O4- + 2MnO4- + 16H+ → 10CO2 + 2Mn2+ + 8H2O
Akhir titrasi ditandai dengan timbulnya warna merah muda yang disebabkan kelebihan permanganat (Day and Underwood, 1980).

Kalium permangatat sukar diperoleh secara sempurna murni dan bebas sama sekali dari mangan oksida. Lagipula, air suling yang biasa mungkin mengandung zat-zat pereduksi yang akan bereaksi dengan kalium permanganat dengan membentuk mangan dioksida serta bukanlah suatu larutan standar primer. (weebly.materi-redoks)

Dalam larutan asam, permanganat (VII) akan tereduksi sehingga tidak berwarna dan bilangan oksidasinya menjadi +2 (ion mangan(II) (Mn2+)).
8 H+ + MnO4− + 5 e− → Mn2+ + 4 H2O
Dalam larutan basa kuat, permanganat (VII) akan tereduksi, warnanya menjadi hijau, dengan bilangan oksidasi +6 (manganat MnO42−).
MnO4− + e− → MnO42−
Dalam larutan netral, ion ini akan tereduksi sehingga bilangan oksidasinya menjadi +4, warnanya hijau (mangan dioksida MnO2).
2 H2O + MnO4− + 3 e− → MnO2 + 4 OH−. (wikipedia Permangana).

Reaksi ini difokuskan pada reaksi oksidasi dan reduksi yang terjadi antara KMnO4 dengan bahan baku tertentu. Titrasi dengan KMnO4 sudah dikenal lebih dari seratus tahun. Kebanyakan titrasi dilakukan dengan cara langsung atas alat yang dapat dioksidasi seperti Fe+, asam atau garam oksalat yang dapat larut dan sebagainya. Beberapa ion logam yang tidak dioksidasi dapat dititrasi secara tidak langsung dengan permanganometri seperti:
(1) ion-ion Ca, Ba, Sr, Pb, Zn, dan Hg (I) yang dapat diendapkan sebagai oksalat. Setelah endapan disaring dan dicuci, dilarutkan dalam H2SO4 berlebih sehingga terbentuk asam oksalat secara kuantitatif. Asam oksalat inilah yang akhirnya dititrasi dan hasil titrasi dapat dihitung banyaknya ion logam yang bersangkutan.
(2) ion-ion Ba dan Pb dapat pula diendapkan sebagai garam khromat. Setelah disaring, dicuci, dan dilarutkan dengan asam, ditambahkan pula larutan baku FeSO4 berlebih. Sebagian Fe2+ dioksidasi oleh khromat tersebut dan sisanya dapat ditentukan banyaknya dengan menitrasinya dengan KMnO4.
Kalium permanganat merupakan oksidator kuat dalam larutan yang bersifat asam lemah, netral atau basa lemah. Titrasi harus dilakukan dalam larutan yang bersifat asam kuat karena reaksi tersebut tidak terjadi bolak-balik, sedangkan potensial elktroda sangat bergantung pada pH. Pereaksi kalium permanganat bukan merupakan larutan baku primer dan karenanya perlu dibakukan terlebih dahulu.

Penentuan-penentuan dengan Permanganat
Penentuan besi dalam bijih-bijih besi adalah salah satu aplikasi terpenting dari titrasi-titrasi permanganate. Asam terbaik untuk melerutkan bijih-bijh besi adalah asm klorida, dan Timah (II) klorida sering ditambahkan untuk membantu proses pelarutan. Sebelum titrasi dengan permanganate setiap besi (III) harus direduksi menjadi besi (II). Timah (II) klorida biasanya dipergunakan untuk mereduksi besi dalam sampel-sampel yang telah dilarutkan dalam asam klorida. Larutan pencegah Zimmermann-Reinhardt lalu ditambahkan jika titrasi akan dilakukan dengan permanganate.
Metode permanganometri didasarkan atas reaksi oksidasi ion permanganat. Oksidasi ini dapat dijalankan dalam suasana asam, netral ataupun alkali. Jika titrasi dilakukan dalam lingkungan asam, maka akan terjadi reaksi
MnO4- + 4 H+ + 3 e à Mn2+ + 4 H2O
Dimana potensial oksidasinya sangat dipengaruhi oleh adanya kepekatan ion hidrogen akan tetapi konsentrasi ion mangan (II) pada persenyawaan di atas tidak terlalu berpengaruh terhadap potensial redoks, karena konsentrasi ion mangan (II) sendiri mampu mereduksi ion permanganat dengan membentuk ion ion Mn3+ dan MnO2. Dalam suasana asam reaksi di atas berjalan sangat lambat, tetapi masih cukup cepat untuk memucatkan warna dari permanganat setelah reaksi sempurna.

Hasil (Inggris) 1:

ANALYSIS of PERMANGANOMETRI
PERMANGANOMETRI




ANALYSIS




Permanganometri SENSE is a redox titration method with reactant MnO4-(permanganate ion). Potassium permanganate is an oxidizing agent that can react in a way that is different, depending on the pH of a solution of it. Her strength as an oxidizing agent that is different according to the reactions that occur at different pH 's. The reaction of various kinds is due to the diversity of the valence of Mn, from 1 to 7 which are all stable except Valence 1 and 5. Reduction of MnO4-takes place as follows:
1. In an atmosphere of sour [H], 0, 1N or more.
MnO4-5e-à 8 h Mn2 4H2O.........................................(1)
2. In a neutral, pH 4-10
4 h-3e MnO4-à 2H2O MnO2................................................(2)
3. In a base [OH-] 0, 1N or more
MnO4-e-à MnO42-
Mostly titration is carried out in an acid according to (1), beside that there are some very important titration in alkaline for organic materials. MnO4-oxidation power in these circumstances is smaller so that the layout of the balance less profitable. To draw the balance towards the results of the titration, titrat plus Ba2 can precipitate MnO42-be BaMnO4. In addition to shifting the balance towards the right, this also prevents the deposition reduction of MnO4-it further. (Harjadi, 1993)
On permanganometri, titran used was potassium permanganate. Potassium permanganate is easily obtained and does not need indicators except a very dilute solution is used and has been used extensively as a reactant oxidation during hundred years more. A drop of permanganate gives a clear pink to a volume of solution in a titration. This color is used to indicate the excess reactant.

Standardised with potassium permanganate using sodium oxalate or as arsenic (III) oxide primary standards. The reaction that occurs in the process of standardisation of potassium permanganate using sodium oxalate is:
5C2O4-2MnO4-16 h → 10CO2 titration 2Mn2 8H2O
End marked by the onset of pink color caused by excess permanganate (Day and Underwood, 1980).

Potassium permangatat hard earned perfectly pure and completely free of manganese oxide. Furthermore, the distilled water which might contain reducing substances that will react with potassium permanganate to form manganese dioxide and is not a primary standard solution. (weebly. redox-material)

In acid solution, permanganate (VII) will be reduced so colorless and varying in oxidation state becomes number 2 (ion of manganese (II) (Mn2)).
8 H MnO4 − 5 e − → Mn2 4 H2O
in aqueous solutions of strong bases, permanganate (VII) will be reduced, its color to green, with oxidation number 6 (MnO42 − manganat).
MnO4 − e − → MnO42 −
ion in aqueous solution is neutral, it will be reduced so that the number varying in oxidation state becomes 4, the colour is green (manganese dioxide MnO2).
2 H2O MnO4 − e − 3 → 4 Oh− MnO2. (wikipedia Permangana).

Reaction is focused on the reduction and oxidation reactions occur between specific raw materials with KMnO4. Titration with KMnO4 has been known for over a hundred years. Most of the titration is done in a straightforward manner on a tool that can be oxidized as Fe, oxalic acid or salts that are soluble and so on. Some metal ions that are not oxidized can be titrated indirectly by permanganometri like:
(1) ions of Ca, Sr, Ba, Pb, Zn, and Hg (I) which can be precipitated as the oxalate. Once filtered and washed sediment, dissolved in excess of H2SO4 so oxalic acid is formed quantitatively. Oxalic acid is titrated and the results of the titration are finally able to count the number of metal ions in question.
(2) ions of Ba and Pb may also be deposited as the salt khromat. Once filtered, washed, and dissolved with acid, the raw FeSO4 solution added to excess. Most of these khromat are oxidized by Fe2 and the rest may be determined as much by menitrasinya with KMnO4.
potassium permanganate is a strong oxidizing in acidic solution of weak, neutral or weakly alkaline. Titration must be carried out in a solution which is a strong acid because the reaction wasn't going back and forth, while the elktroda potential is very dependent on pH. Potassium permanganate reagents is not a solution of the primary raw and therefore need to be standardized in advance. the determinations of

Permanganate
determination of iron in iron ore-ore is one of the most important applications of titration-permanganate titration. Best acid for iron-ore melerutkan-bijh is a asm chloride, and Tin (II) chloride is often added to help the dissolving process. Prior to titration with permanganate per iron (III) must be reduced to iron (II). Tin (II) chloride is usually used to reduce iron in the samples which had been dissolved in hydrochloric acid. Preventive solution Zimmermann-Reinhardt added if the titration should be done with permanganate.
Permanganometri method based on permanganate ion oxidation reactions. This oxidation can be run in an atmosphere of acid, neutral or alkaline. If the titration is carried out in an acid environment, then there will be reaction MnO4-4 H
3 e
à Mn2 4 H2OWhere potential varying in oxidation state are strongly influenced by the presence of hydrogen ion densities, but the concentration of manganese (II) ions on the fertilization in the not-too-influential redox potential, due to the concentration of manganese (II) ions alone are capable of the reduction of permanganate ion to form the ion the ion Mn3 and MnO2. In the above reaction acid atmosphere goes very slow, but it is still fast enough to memucatkan the color of permanganate after perfect reaction.

Hasil (Inggris) 2:

PERMANGANOMETRI ANALYSIS
ANALYSIS PERMANGANOMETRI DEFINITIONS Permanganometri is a redox titration method with reagent MnO4-(ion permanganate). Potassium permanganate is an oxidizing agent that can react in different ways, depending on the pH of the solution. Its strength as an oxidant which vary according to the reactions that occur at different pH's. The reaction is caused by a wide range of diversity valence of Mn, from 1 to 7 are all stable except valence 1 and 5. MnO4-reduction takes place as follows: 1. In acid [H +], 0.1 N or more. MnO4-+ 8H + + 5e-Mn2 + + 4H2O à .......................... ............... (1) 2. In neutral, pH 4-10 MnO4-+ 4H + + 3e-MnO2 + 2H2O à ............................... ................. (2) 3. Under alkaline conditions [OH-] 0.1 N or more MnO4-+ e-à-MnO42 Most titrations carried out in an acid according to (1), besides that there are some very important titration in alkaline conditions for organic materials. MnO4-oxidation power in the state is smaller so the balance is less favorable position. To attract towards balance of the titration results, titrat plus Ba2 + can precipitate MnO42-be BaMnO4. In addition to shifting the balance towards the right, it also prevents the deposition of MnO4-reduction it further. (Harjadi, 1993) In permanganometri, titrant used is potassium permanganate. Potassium permanganate is easy to obtain and does not require an indicator unless used very dilute solutions and has been used extensively as an oxidizing reagent for a hundred years more. A drop of permanganate gives a clear pink color to the volume of the solution in a titration. This color is used to indicate the excess reagent. Potassium Permanganate standardized using sodium oxalate or as arsenic (III) oxide is the primary standards. Reactions that occur in the process of standardization of potassium permanganate using sodium oxalate is: 5C2O4-+ 2MnO4-+ 16H + → 10CO2 + 2Mn2 + + 8H2O Final titration is marked by the onset of pink color due to excess permanganate (Day and Underwood, 1980). Potassium permangatat difficult to obtain perfectly pure and free from manganese oxide. Moreover, ordinary distilled water may contain reducing substances that will react with potassium permanganate to form manganese dioxide and is not a primary standard solution. (Weebly.materi-redox) In acidic solution, permanganate (VII) is reduced to a colorless and become a +2 oxidation number (ion manganese (II) (Mn 2 +)). 8 H + + MnO4-+ 5 e-→ Mn2 + + 4 H2O In a strong alkaline solution, permanganate (VII) will be reduced, the color is green, with a +6 oxidation number (MnO42-manganate). MnO4-+ e-→ MnO42- In neutral solution, this ion will be reduced so that the oxidation number +4 , color green (manganese dioxide MnO2). 2 H2O + MnO4-+ 3 e-→ MnO2 + 4 OH-. (Wikipedia Permangana). reaction is focused on oxidation and reduction reactions that occur between KMnO4 with certain raw materials. Titration with KMnO4 has been known for more than a hundred years. Mostly done by direct titration of the means that can be oxidized as Fe +, oxalic acid or soluble salt and so on. Some of the non-oxidized metal ions can be titrated indirectly by permanganometri as: (1) the ions Ca, Ba, Sr, Pb, Zn, and Hg (I) which can be precipitated as the oxalate. After the precipitate is filtered and washed, dissolved in excess H2SO4 to form oxalic acid quantitatively. Oxalic acid is what ultimately titrated and the results of the titration can be calculated amount of metal ions in question. (2) ions Ba and Pb can also be precipitated as chromate salts. Once filtered, washed, and dissolved with acid, also added standard solution excess FeSO4. Most of Fe 2 + is oxidized by chromate and the remaining amount can be determined by menitrasinya with KMnO4. Potassium permanganate is a strong oxidizing agent in the solution is weakly acidic, neutral or weak base. Titration should be carried out in a strong acidic solution because the reaction does not occur back and forth, while the potential elktroda highly dependent on pH. Reagent potassium permanganate is not a primary standard solution and hence need to be standardized first. determination-determination by Permanganate Determination of iron in iron ores is one of the most important applications of permanganate titrations. Best acid-bijh melerutkan iron ore is asm chloride, and tin (II) chloride is often added to aid dissolution. Before titration with permanganate each iron (III) must be reduced to iron (II). Tin (II) chloride is usually used to reduce iron in the samples that had been dissolved in hydrochloric acid. Zimmermann-Reinhardt prevention solution is then added if the titration will be performed with permanganate. permanganometri method based on the reaction of permanganate ion oxidation. This oxidation can be carried out under acidic, neutral or alkaline. If the titration carried out in an acidic environment, there will be a reaction MnO4-+ 4 H + + 3 e à Mn2 + + 4 H2O Where potential oxidation greatly influenced by the concentration of hydrogen ions but ion concentration of manganese (II) compounds above does not significantly affect redox potential, because the ion concentration of manganese (II) alone can reduce permanganate ion to form Mn3 + ions and MnO2. Under acidic reaction upon running very slow, but still fast enough to memucatkan color of permanganate after complete reaction.