Makalah Golongan 3 B.docx

MAKALAH KIMIA ANORGANIK II UNSUR-UNSUR TRANSISI III (Golongan III B)

DISUSUN OLEH : Kelompok I: Lia Agustini

(06121010007)

Ranny Rolinda Rusman (06121010020) Arum Estu Tami

(06121010028)

DOSEN PENGASUH : Prof. DR. Fakhili Gulo, M.Si.

PROGRAM STUDI PENDIDIKAN KIMIA FAKULTAS KEGURUAN DAN ILMU PENDIDIKAN UNIVERSITAS SRIWIJAYA 2014

KATA PENGANTAR

Puji syukur kehadirat Allah SWT, karena berkat rahmat dan karunia-Nya jualah penulis dapat menyelesaikan pembuatan makalah ini. Tak lupa penulis mengucapkan terima kasih kepada Bapak Prof. Dr. Fakhili

Gulo,

M.Si. dan

teman-teman

mahasiswa

pendidikan

Kimia

angkatan 2012, yang tiada henti memberikan dukungan dan motivasinya, serta pihak lain yang terkait demi terselesaikanya makalah ini. Layaknya kata pepatah, Tak ada gading yang tak retak. Demikian jugalah ungkapan yang tepat untuk makalah ini. Apabila dalam makalah ini terdapat kesalahan baik dalam bentuk penulisanya maupun ejaan dan bahasanya, maka penulis mohon maaf yang setulusnya. Dan tentu saja kritik dan saran yang bersifat membangun dari pembaca sekalian amat kami harapkan. Semoga makalah ini dapat bermanfaat dan berguna sebagaimana mestinya. Demikianlah sepatah kata yang penulis sampaikan. Atas perhatian pembaca sekalian, penulis mengucapkan terima kasih. Inderalaya, 09 Oktober 2014

Penulis

Daftar Isi

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Kata Pengantar ................................................................................................ ii Daftar Isi............................................................................................................iii BAB I Pendahuluan ........................................................................................ 1 1. 2. 3. 4.

Scandium............................................................................................... 2 Yttrium.................................................................................................. 3 Lanthanum............................................................................................ 13 Actinium................................................................................................ 17

BAB II Pembahasan ........................................................................................ 20 BAB III Penutup .............................................................................................. 22 1. Kesimpulan ........................................................................................... 22 2. Saran ..................................................................................................... 22 Daftar Pustaka ................................................................................................. 23

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BAB I PENDAHULUAN 1.

Latar Belakang Sangat banyak unsur-unsur yang dapat ditemui di alam ini. Sampai saat ini

saja sudah 112 unsur telah ditemukan oleh para ahli. Unsur-unsur tersebut memiliki sifat dan karakteristik yang berbeda-beda yang menyebabkan sulit untuk mempelajarinya. Oleh karena itu, untuk memudahkan dalam mempelajari unsurunsur tersebut, para ahli telah berupaya untuk mengelompokkan unsur-unsur tersebut

berdasarkan

kemiripan

sifat

dan

karakteristik

unsure-unsur

tersebut. Berdasarkan pernyataan di atas maka penulis tertarik untuk membuat sebuah makalah yang berjudul “Unsur Golongan IIIB”. Dalam makalah ini terdapat materi mengenai sejarah unsur golongan IIIB dan reaksi mengenai unsur golongan IIIB. II. Tujuan Tujuan pembuatan makalah ini adalah untuk memenuhi tugas yang diberikan oleh dosen mata kuliah Kimia Anorganik II tantang unsure golongan IIIB.

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BAB III ISI UNSUR-UNSUR GOLONGAN III B Comparison of properties of the IIIB Group Elements a. Atomic size In one class, from top to bottom fingers growing larger, the more the number of electron shells. Meanwhile, in a period, from left to right fingers getting shorter, because the size of the core of the right to be even greater, with the core appeal of the stronger electron. b. density In one class from top to bottom the greater density. This is because the relative atomic mass that occupies the greater but that is almost the same volume. c. Ionization energy Ionization energy is the energy required to remove an electron is bound to be weaker than a neutral atom or in a gaseous state. In one class, from top to bottom value of the ionization energy decreases IIIB group elements, because from top to bottom atomic radius so that the greater the attractiveness of the core with the outer electrons is weak, then the smaller the ionization energy. d. Electronegativity Electronegativity is the ability of an atom to attract electrons from the atoms of the element lain.Dalam one class, from top to bottom of group IIIB elements electronegativity is getting smaller, because the larger the radius, the greater the volume and the attractiveness of the nucleus and the electrons is weak.

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1. Scandium Energy First

Level: 4 Energy

Level: 2

Second

Energy

Level: 8

Third

Energy

Level: 9

Forth Energy Level: 2 1.1.

History (Latin: scandia, Scandinavia). Mendeleev predicted the existence of

elements of the periodic system ekaboron based on the principle of the invention. This element has an atomic weight estimated between 40 (calcium) and 48 (titanium). Scandium element was discovered by Nilson in 1878 in the minerals and gadolinite euxenite, which has never been found anywhere except in Scandinavia. By processing 10 kg of byproduct euxenite and other rare minerals, Nilson was able to produce 2 grams of pure scandium oxide. Subsequent scientists then showed that the same Nilson discovered scandium with ekaboronnya Mendeleev. 1.2.

Discovery Scandium is a group IIIB elements that are in the period of 4 Scandium is

part of the transition elements. Scandium was discovered by Lars Nilson in 1879 in Sweden. Scandium is found in minerals euxenite, thortveitile, thortvetile and Gadoline in Scandinavia and Madagascar. Fredik Lars Nilson and his team are not aware of the predictions on the source in 1879, which contained a little investigating metal on earth. With spectral analysis they discovered a new element in the mineral earth. They named scandium from Latin Scandia meaning Scandinavia and in the process of isolation, they process 10 kg euxenite, generating approximately 2 g of pure scandium oxide (Sc2O3). This element is named in honor of Scandium as the Scandinavian countries where the discovery of this element. Dmitri Mendeleev periodic element used in 1869 to predict the circumstances and the nature of the three elements is called ekaboron.Fischer,

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Brunger, and scandium Grinelaus process for the first time in 1937, by electrolysis of potassium, lithium, and scandium chlorides at temperatures 700-800ºC. 1.3. Nature-properties Scandium is a silver-white metal that change color to yellow or kemerahjambuan if exposed to air. These elements are soft and more resembles yttrium and rare metals other than aluminum or titanium. He lightweight and has a higher boiling point than aluminum, making it a highly desirable material by perangcang spacecraft. Scandium is not attacked with a mixture of 1: 1 HNO3 and 48% HF. Physical Properties 1. Density

: 3 g/cm3

2. Melting Point

: 1812,2 K

3. Boiling Point

: 3021 K

4. Form (25°C)

: solid

5. Color

: silvery white

Atomic Properties 1. Atomic Number

: 21

2. Mass Number

: 44,956

3. Electron configuration

: [Ar] 3d1 4s2

4. Atomic Volume

: 15 cm3/mol

5. Electron Afinity 6. Electronegativity

: 18,1 kJ/mol : 1,36

7. Ionisation Energy : - First : 631 kJ/mol, Second 2389 kJ/mol 8. Primary oxydation number

: +3

9. Other Oxydation Number : +1, +2 10. Crystal form

: Hexagonal Unit Cell

Chemical Properties and Reactions

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: 1235 kJ/mol, Third :

Chemical properties of Scandium:  Reaction with water: When heated, the Scandium will dissolve in water to form a solution consisting of ions Sc (III) and hydrogen gas 2Sc (s) + 6H2O (aq) ---> 2Sc3 + (aq) + 6OH- (aq) + 3H2 (g)  Reaction with oxygen In the reaction with the combustion air or quickly it will form scandium (III) oxide 4SC (s) + 3O2 (g) ---> 2Sc2O3 (s)  Reactions with halogens Scandium is very reactive w/hen it reacts with all the halogens to form trihalides elements 2Sc (s) + 3F2 (g) ---> 2ScF3 (s) 2Sc (s) + 3Cl2 (g) ---> 2ScCl3 (s) 2Sc (s) + 3Br2 (l) ---> 2ScBr3 (s) 2Sc (s) + 3I2 (s) ---> 2ScI3 (s)  The reaction with acid Scandium klrida soluble in acid to form a solution containing ions Sc (III) and hydrogen gas Sc (s) + 6HCl (aq) ---> 2Sc3 + (aq) + 6Cl- (aq) + 3H2 (g) 1.4. Scandium compounds One form of the compounds found in the element Scandium is Scandium cloride (ScCl3), Metals can also be obtained through the electrolysis process with the following reaction:

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2Sc (s) + 3 Cl3 (g) → 2ScCl3 (s) This comes from the electrolysis of molten potassium, lithium, scandium chloride at a temperature of 700-800 0C. The research was conducted by Fischer, Brunger, Grieneisen. 1.5 Useful  Clorida Scandium (ScCl3), where these compounds can be found in halide lamps, fiber optic, and laser ceramic electrolyte.  Primary application of the elements scandium alloy alumunium- dalah as scandium is used in the aerospace industry and for sports equipment (bikes, baseball bats) that have a high quality.  Other applications is the use of scandium iodide for lights that provide a high intensity. Sc2O3 is used as a catalyst in the manufacture of Acetone Health and the Environment Effect

1.6.

Scandium is not toxic, but need to be careful because some scandium compounds may be carcinogenic in humans but it can cause liver damage if it accumulates in the body. Together with aquatic animals, Sc can cause damage to the cell membrane, thus providing a negative effect on the reproductive and nervous systems. Sc can contaminate the environment, especially from the petroleum industry and from the disposal of household furniture. Sc continuously accumulate in the soil, it will trigger the concentration in the human body and animals. 2. YITRIUM (Yttrium) Currently yttrium (the name of a Swedish village, Ytterby) widely known in its use as superconducting oxides (along with barium and copper). This is the first superconducting material that functions at liquid nitrogen temperatures. The element was discovered in 1789 by Gadolin and finally isolated in 1828 by Wöhler. More than 15 tons of oxides are now manufactured every year. In

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addition to its use in the study of superconductivity, is also used in phosphors (red) for color television tubes. Yttrium is a silvery metal. Most commercially produced daripasir yttrium monazite which is also the source for most of the elements of the soil. Yttrium has a silvery-metallic luster. Yttrium lit up in the air. Yttrium is found in the minerals of the earth. Moon rocks contain yttrium and yttrium is used as a Tabel: Basic Information dan Classification of Yttrium

Name : Yttrium

Group in periodic Table : 3

Symbol : Y

Period in Periodic Table : 5

Atomic Number : 39

Block in Periodic Table : d-block

Atomic Mass : 88,90585 (2)

Color : silvery white

Standard Form : solid in 298 K

Classification : metal

This sample is from the Element Collection, an attractive and safely packaged collection of 92 natural elements are available for sale. 2.1 Invention Yttrium is a group IIIB element residing in the period 5. Yttrium included in the transition metal. Yttrium was discovered by researchers from Finland named Johan Gadolin and isolated in 1794 by Friedrich Wohler in 1828 in the form of impure extract of yttria from yttrium chloride anhydrous reduction (YCl3) with potassium. Gadolin Johan Friedrich Wohler Yttria (YCl3) is the oxide of yttrium and discovered by Johan Gadolin in 1794 in the mineral gadolinite of Yttreby, Sweden. In 1843 a Swedish chemist Carl Mosander can show that yttria can be divided into oxides in three different 23

elements called Yttria. Mining is located near the village of Ytterby which resulted in some minerals such as erbium, terbium, ytterbium, and yttrium has the same name as the village. Carl Mosander These compounds are named in honor of the city Yttrium because Ytterby in Sweden. This compound is found in the rare minerals found on earth (including monazite, xenotime, Yttria). This compound is not found in a free state on earth. 2.2. The Properties of Yttrium  1. 2. 3. 4. 5. 6.

Physical Properties Density: 4.5 g / cm 3 Melting point: 1799 [or 1526 ° C (2779 ° F)] K Boiling point: 3609 [or 3336 ° C (6037 ° F)] K Form 4 (25 ° C): solid Color: silver Temperature superconducting: 1.3 [or -271.85 ° C (-457.33 ° F)] (under

 1. 2. 3. 4. 5.

pressure) K Atomic nature Atomic number: 39 Mass number: 88.91 Electron Configuration: [Kr] 4d1 5s2 Atomic volume: 19.8 cm 3 / mol Electron affinity: 29.6 kJ / mol Definitions that are used most of electronegativity is that an element's

electronegativity is the power of an atom when in a molecule to attract electron density to itself. electronegativity depends on a number of factors and elaborate as the other atoms in the molecule. The first scale of electronegativity was developed by Linus Pauling and scale yttrium has a value of 1.22 on a scale running from from about 0.7 (an estimate of francium) to 2.20 (for hydrogen) to 3.98 (fluorine). Electronegativity has no units but "Pauling units" are often used when indicating values mapped to the Pauling scale. On the interactive plot below you may find the "Ball chart" and "Shaded table" styles most useful. At an interactive point can be seen in the chart below diagrams and tables are useful.

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Tabel Some Electronegativity for Yttrium Electronegativity

Nilai dalam satuan Pauling

Pauling Electronegativity

1,22

Sanderson electroegativity

0.65

Rochow Allred Negativity

1,11

There are a number of ways to produce a set of numbers representing electronegativity and three are given in the table above. Pauling scale is perhaps the most famous and sufficient for many purposes. 7. Ionisation energy:  First: 615.6 kJ / mol  Second: 1181 kJ / mol  Third: 1979.9 kJ / mol 8. Main oxidation states: +3 9. Other oxidation states: +2 10. Form of Structure: Hexagonal Unit Cell  Chemical Properties Chemical properties of Yttrium are:  Reaction with water When heated it Yttrium metal will dissolve in water to form a solution consisting of ion Y (III) and hydrogen gas 2Y (s) + 6H2O (aq) → 2Y3 + (aq) + 6OH- (aq) + 3H2 (g)  Reaction with oxygen In the reaction with the combustion air or quickly it will form Yttrium (III) oxide 4Y (s) + 3O2 (g) → 2Y2O3 (s)  Reactions with halogens Yttrium is very reactive when it reacts with all the halogens to form trihalides elements 2Y (s) + 3F2 (g) → 2YF3 (s) 23

2Y (s) + 3Cl2 (g) → 2YCl3 (s) 2Y (s) + 3Br2 (g) → 2YBr3 (s) 2Y (s) + 3I2 (g) → 2YI3 (s)  Reaction with acids Yttrium klrida soluble in acid to form a solution containing ions of Y (III) and hydrogen gas 2Y (s) + 6HCl (aq) → 2Y3 + (aq) + 6Cl- (aq) + 3H2 (g) 2.3. Yttrium Compounds Yttrium metal is available commercially so it is not necessary to make it in the laboratory. Yttrium is found in the mineral extraction lathanoid and yttrium and lanthanoid metals from ores is very complex. This is an extract metals from ores by salt extraction with sulfuric acid (H 2 SO 4), hydrochloric acid (HCl), and sodium hydroxide (NaOH). Modern techniques for the purification of these lanthanoid salt mixtures involve selective complexation techniques, solvent extraction and ion exchange chromatography. Pure yttrium available through the reduction of YF 3 with calcium metal. 2YF 3 + 3Ca → 2Y + 3CaF 2 2YF 3 + 2y + 3Ca → 3CaF 2 Yttria (yttrium oxide, Y 2 O 3), was discovered by Johann Gadolin in 1794 in a mineral called gadolinite of Ytterby. Ytterby is the site of a mine in Sweden which contains many unusual minerals containing erbium, Terbium and ytterbium and yttrium. Friedrich Wohler states obtained pure element in 1828 by reduction of chloride anhydrous (YCL 3) with potassium. Yttrium compounds usually found in the form of compounds - Yttrium garnet Allumunium Y¬3All5O12 - Yttrium (III) Oxide Y2O3

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This section lists some binary compounds with halogens (known as halides), oxygen (known as oxides), hydrogen (known as hydrides), and some other compounds of yttrium. For each compound, a formal oxidation number for yttrium given, but the usefulness of this number is limited for p-block elements in particular. Based on oxidation number, an electron configuration is also given but note that for the other components, is seen as a guide only. The term hydride is used in a generic sense to indicate compounds of the type M x H y and not necessary to indicate that any compounds listed behave chemically as hydrides. In the compound of yttrium, usually largely yttrium oxidation number is: 3. Hydride The term hydride is used in a generic sense to indicate compounds of the type M x H y and not necessary to indicate that any compounds listed behave chemically as hydrides. • Yttrium dihidrida: YH 2 • Yttrium trihydride: YH 3 Fluoride, Chloride, Bromide, Iodide Yttrium is very reactive to the halogens; fluorine, F 2; chlorine, Cl 2; bromine, Br 2; and iodine, I 2, to form the trihalides yttrium (III) fluoride, YF 3; yttrium (III) chloride, YCL 3; yttrium (III) bromide, YBR 3; and yttrium (III) iodide, YI 3. 2Y (s) + 3F 2 (g) → 3 2YF (s) 2Y (s) + 3Cl 2 (g) → 3 2YCl (s) 2Y (s) + 3br 2 (g) → 3 2YBr (s) 2Y (s) + 3I 2 (g) → 3 2YI (s) • Yttrium triflourida: YF 3 • Yttrium trichloride: YCL 3

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• Yttrium tribromide: YBR 3 • Yttrium triiodide: YI 3 Oxide • Metal Yttrium reacts slowly in the air and its reaction with oxygen to form yttrium (III) oxide, Y 2 O 3 Or Diyttrium trioxide: Y 2 O 3 4Y + 3O 2 → 2Y 2 O 3 sulfide • Diyttrium trisulphide: Y 2 S 3 complex • Diyttrium trisulphate octahydrate: Y 2 (SO 4) 3. 4/5 H 2 O • Yttrium trinitrate hexahydrate: Y (NO 3) 3 .3 / H 2 O 5 2.4. usage - Yttrium garnet Allumunium Y¬3All5O12 this compound is used as a laser in addition to diamond jewelry that stimulants on. - Yttrium (III) Oxide Y2O3 compound is used to make YVO4 (Eu + Y2O3) Eu phosphor which gives the red color in color TV tubes. Yttrium oxide is also used to make Yttrium-Iron-garnet were used in the microwave to be effective - In addition, Yttrium is also used to increase the strength of the metals aluminum and magnesium alloy. Addition of Yttrium on iron has made his effectiveness in working. 2.5. For Health and Environmental Effects Yttrium danger if the moisture in the air is if inhaled by humans can cause cancer and if it accumulates in excess amounts in the body causing damage to the liver. On exposure to water the animals Yttrium cause damage to the cell membrane, which affects the reproductive system and the function of the nervous

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system. Yttrium is not toxic but some of scandium compounds are carcinogenic in humans but it can cause liver damage if it accumulates in the body. Yttrium can contaminate the environment, especially from the petroleum industry and from the disposal of household furniture. Yttrium continuously accumulate in the soil, it will trigger the concentration in the human body and animals. 3.LANTHANUM 3.1. General Description Lanthanum is a chemical element with the symbol La and atomic number 57. Lanthanum is a silvery white metallic element that is owned by a group 3 of the periodic table and the lanthanides. Lanthanum is a soft metal, ductile, and soft which quickly oxidize when exposed to air. It is produced from the mineral monazite and bastnasite using a complex multistage extraction process. Lanthanum compounds have many applications as catalysts, additives in glass, carbon lighting for studio lighting and projection, ignition elements in lighters and torches, electron cathodes, scintillators, and others. Lanthanum carbonate (La2 (CO3) 3) was approved as a treatment for kidney failure. 3.2. History and Discovery A Swedish chemist, Carl Gustav Mosander which is a great chemist with the nickname "father moses" in 1893 has found a new element in the form of a sample of cerium nitrate impuritif. Lanthanum was discovered by the Swedish chemist of this when he changed the composition of the sample of cerium nitrate by heating and reacting the salt with dilute nitric acid. From the results of the reaction and isolate the so-called lantana. Lanthanum was isolated in pure form in 1923. Then he gave the name to the "Lanthana" which means "hidden". The mineral is now known as Lanthanum oxide, La2O3. The pure metal is not / can not be isolated up to 1923.

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Lanthanum is the first element in a series of elements called "Lanthanida" .Which often called the goal "rare earth" minerals or rare. Y and La are almost always affiliated with the group Lanthanida. He is white silver, soft, and quite easily sliced with a regular knife. The entire group IIIB metals in easily arise if the staining in the air, and flammable as La2O3. Separation operated commercially include deposition of a weak base solution with the addition of magnesium oxide nitrate or ammonia gas. Purification lanthanium remain in solution conditions. Another way fractional crystallization made by Dimitry Mendeleev, in the form of double ammonium nitrate tetrahydrate, which is used for separating the lanthanum that has a small solubility of didymium which has a greater solubility in the system 1870 is used commercially in lanthanum purification until the development of the solvent extraction method which began in 1950 As the purification of lanthanum, ammonium nitrate direkristalisaikan of water. Lanthanum is relatively easily purified, since there is only one adjacent lanthanide cerium is very easily separated according to the valence bond. 3.3. PHYSICAL AND CHEMICAL PROPERTIES PHYSICAL PROPERTIES Lanthanum is a silvery white metal, malleable, strong but soft enough to cut with a knife. He is one of the highly reactive metals. He oxidizing rapidly when exposed to air. Lanthanum has a density of 6.17 g / cm 3. , Has a melting point of 1193.2 K and a boiling point of 3693 K. CHEMICAL PROPERTIES - Reaction with water Lanthanum is quite electropositive and reacts slowly with cold water but fairly quickly if it reacts with hot water to form hydrogen gas and hydroxide Lanthana 2LA (s) + 6H2O (g) 2La (OH) 3 (aq) + 3H2 (g)

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- Reaction with oxygen In the reaction with the combustion air or quickly it will form Lanthana (III) oxide. 4LA (s) + 3O2 (g)  2La2O3 (s) - Reactions with halogens Lanthanum metal reacts with all the halogen elements form Lanthana (III) halide 2LA (s) + 3F2 (g)  2LaF3 (s) 2LA (s) + 3Cl2 (g)  2LaCl3 (s) 2LA (s) + 3Br2 (g) 2LaBr3 (s) 2LA (s) + 3I2 (g)  2LaI3 (s) 3.4. USE Rarely La pure metal or oxide compound has a specific purpose. Because the chemical elements have in common, they are very difficult to separate. The mixture will be termaanfaatkan of the pure form. for example: "misch metal" is a mix of some "rare earth" and is commonly used for "lighter flints' and forms of phosphorus oxidation is also used in television screens (LaMgAl11O19) and some similar fluorescence equipment. La2O2 is used to create a special optical glass (glass adsorbs infrared, camera and telescope lenses). If La is added in the steel will increase the softness and durability of the steel. He was used as the main material in the carbon electrode (carbon arc electrodes). La salts contained in the zeolite catalysts used in petroleum pengkilangan process. One of the uses of the compounds Lanthanida goal is in the film industry for studio lighting and projection. Lanthanum can adsorb H2 gas so that the metal is called the "hydrogen sponge" or a hydrogen sponge. H2 gas is dissociated into atomic H, which will fill

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most of the room (interstice) in the La atoms. When the H atom escape back into the air then they re-join the HH bond. E. For Health and Environmental Effects It is very dangerous and the smoke inhaled mist jikak with the influx of oxygen and in the long term, will be able to cause embolism. If the person can breathe La affected by lung cancer. If accumulates in the body, the La-threatening liver organ. It can contaminate the environment, especially from the petroleum industry and from the disposal of household furniture. He continuously accumulate in the soil, it will trigger the concentration in the human body and animals. Together with aquatic animals, La can cause damage to the cell membrane, thus providing a negative effect on the reproductive and nervous systems. He is very easy to accumulate in the muscles. 3.5. CHEMICAL REACTION - Lanthanum combustible at 150 ° C to form lanthanum (III) oxide 4 La + 3 O2 → 2 La2O3 + La + 3O2 → 4 2LaO2 However, when exposed to moist air at room temperature, lanthanum oxide form a hydrated oxide with a large volume increase.

- Lanthanum is quite electropositive and reacts slowly with cold water and quite quickly with hot water to form lanthanum hydroxide: 2LA (s) + 6H2O (l) → 2LA (OH) 3 (aq) + 3H2 (g) + 2LA (s) + 6H2O (l) → 2LA (OH) 3 (aq) + 3H 2 (g) - Lanthanum easily soluble in dilute sulfuric acid to form solutions containing the La (III) ions, which exist as [La (OH2) 9] 3 + complexes 2LA (s) + 3H2SO4 (aq) → 2La3 + (aq) + 3SO4 2- (aq) + 3H2 (g) + 2LA (s) + 3 H 2SO 4 (aq) →

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2LA 3 + (aq) + 3SO4 2- (aq) + 3H2 (g) 4. Actinium 4.1. General Description Actinium (pronounced / æktɪniəm / ak-TIN-nee-É ™ m) is a radioactive chemical element with the symbol Ac and atomic number 89, discovered in 1899 actinium Actinides are elements of the group, a group of 15 similar elements between actinium and lawrencium in Table periodic. Actinium, named aktinos of bahasaYunani. Actinium is also a rare radioactive metal that glows in the dark. Actinium isotope longest life (Ac-227) has a half-life of 21.8 years. This element is obtained as impurities in pitchblende, an ore mined for uranium content. Onetenth of a gram of actinium can be recovered from 1 ton of pitchblende. 4.2. Origin of the Invention Actinium was discovered in 1899 by Andre-Louis Debierne a French chemist who separates from the mixture actinium. Actinium is separated from uranium ores, in 1899 explained that actinium is similar to titanium and in 1900 explained that actinium is similar to thorium. Then Friedrich Oskar Giesel independently discovered actinium in 1902 as a substance that is similar to lanthanum and called it "emanium" in 1904 After the comparison substances in 1904, the name was retained because Debierne seniority. Actinium chemical properties similar to lanthanum. The word actinium comes from the Greek, activism, aktinos, which means light. Because Ac is a radioactive element that can be glow in the dark room, which is caused by the intensity of radioactivity is blue. Actinium is found in a number of sedukit in uranium ores but many more were made in units of mg by means of neutron irradiation of 226 Ra in a nuclear reactor. Actinium metal is made by way of reduction of actinium fluoride with lithium vapor at temperatures 1100-1300ºC. 4.3. Chemical Properties Actinium shows chemical properties similar to lanthanum. Because of this similarity the separation of actinium from lanthanum and other rare earth elements, which are also present in uranium ore becomes difficult. Solvent 23

extraction and ion exchange chromatography is used for separation. Only a number of actinium compounds are known, such as ACF 3, AcCl 3, AcBr 3, AcOF, AcOCl, AcOBr, Ac 2 S3, Ac2O, and AcPO3. All the mentioned compound is similar to the compounds of lanthanum and actinium shows that compounds generally have an oxidation number of +3. 4.4. Physical Properties 1. 2. 3. 4. 5. 6. 7. 8.

Density: 10 g / cm 3 Melting Point: 1323.2 K Boiling Point: 2743 K Form (25 ° C): solid Color: white silver Melting Heat : 14 kJ mol -1 Heat of evaporation: 400 kJ mol -1 Material Capacity: (25 ° C) 27.2 J mol -1 K -1

4.5. useful The nature of radioactivity of actinium 150 times larger than radium, making it possible to use AC as a neutron source. Instead, actinium is rarely used in the field of industry. Ac-225 is used in the treatment, which is used in a generator to produce Bi-213. Ac-225 can also be used as a healing agent for the "radio-immunotherapy". 4.6. Health and Environmental Effects Actinium-227 is highly radioactive and adverse health effects. Danger of actinium is equal to the danger of plutonium. The greatest danger of raioaktif transform life as we know it is a danger to the reproductive system and the nature of the decline. Even with low-dose carcinogenic which causes a decrease in the immune system. The growth of nuclear technology has brought a large amount of radioactive substances into the atmosphere expenditures, land, and sea. Harmful radiation and are concentrated in the food chain, so harmful to humans and animals. 4.7. Chemical Reactions

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 Reaction with oxygen Actinium actinium flammable form (III) oxide 4ac (s) + 3O2 (g) → 2Ac2O3 (s) Actinium compounds For example ACF 3, AcCl 3, AcBr 3, AcOF, AcOCl, AcOBr, Ac 2 S 3, Ac2O, and AcPO3.

 Actinium-227 is highly radioactive and adverse health effects.  The greatest danger from radioactive transform life as we know it is a danger to the reproductive system and the nature of the decline.  Even with low-dose carcinogenic which causes a decrease in the immune system.

BAB III PEMBAHASAN Bab ini berisi pembahasan dari pertayaan dan jawaban selama kegiatan diskusi. Pertanyaan yang diajukan oleh beberapa peserta diskusi dan dijawab oleh kelompok penyaji. 23

1. Nurbaiti: Pertanyaan:  Mengapa unsur transisi dimulai dari golongan III B?  Senyawa scandium apa yang bersifat karsinogenik? Apa

yang

menyebabkan sifat karsinogen tersebut?  Mengapa scandium yang bersifat kuat bisa dipotong dengan pisau dengan mudah?  Mengapa lanthanum bereaksi cepat dengan air panas tetapi lambat denngan air dingin? Jawaban:  Golongan-golongan B terletak antara golongan IIA dan IIIA. Unsureunsur tersebut merupakan peralihan dari golongan IIA ke golongan IIIA, yaitu unsure-unsur yang dialihkan hingga di temukan unsure yang mempunyai kemiripan sikap dengan golongan IIIA. Periode ketiga golongan IIA ditempati oleh magnesim (nomor atom 12), sedangkan golongan IIIAoleh aluminium (nomor atom 13). Pada periode keempat, golongan IIA ditempati oleh kalsium (nomoratom 20). Namun demikian, unsure

berikutnya,

yaitu

scandium

(nomor

atom

21),

tidak

menunjukkankemiripan sifat dengan aluminium. Oleh karena itu, scandium tidak dapat ditempatkan di bawahaluminium pada golongan IIIA. Ternyata, 10 unsur harus dialihkan hingga ditemukan gallium (nomoratom 31) yang menunjukkan kemiripan sifat dengan aluminium. Kesepuluh unsure tersebt merupkanunsure transisi periode 4.  Sc2O3, Na3ScF6, Sc(OH)3  Mudah dipotong karena ikatan logamnya lemah  Lanthanum cukup elektropositif dan bereaksi secara lambat dengan air dingin tapi cukup cepat jika bereaksi dengan air panas membentuk lanthana hidroksida dan gas hydrogen. Air dingin menyerang lantanium secara pelan-pelan, sedangkan air panas dengan sangat cepat. Lanthanum cukup elektropositif dan bereaksi lambat dengan air dingin dan cukup cepat dengan air panas untuk membentuk lantanum hidroksida. 2. Leo Saputra Simanjuntak 23

Pertanyaan: Unsur Lantanum dan Actinium termasuk dalam golongan Lantanida dan Actinida, kenapa dalam tabel periodik unsur dimasukkan dalam golonga III B sedang lantanida dan aktinida yang lain diletakkan dalam penggolongan yang berbeda? Jawaban: Semua unsure transisi dalam sebenarnya menempati golongan IIIB, yaitu lantanida pada periode keenam dan aktinida pada periode ketujuh. Jadi, golongan IIIB periode keenam dan periode ketujuh, masing-masing berisi 15 unsur. Unsure-unsur transisi dalam memiliki sifat-sifat yang sangat bermiripan sehingga ditempatkan dalam satu kotak. Alasan pemisahan unsur-unsur lantanida dan ktinida lain dari golonngan 3 B adalah untuk menyederhanakan tampilan dari system periodic unsur. 3. Nurul Safitry Pertanyaan: Bagaiman kelimpahan dari unsur-unsur golongan III B? Bagaiman pula kelimpahan dari isotop-isotop dari unsur golongan III B? Jawaban: Unsur-unsur golongan III B memiliki kelimpahan yang sedikit di muka bumi. Begitu pula dengan isotp dari unsur-usur dalam golongan ini.

PENUTUP I. Kesimpulan Sifat Unsur-Unsur Golongan IIIB 1. Dalam satu golongan, dari atas ke bawah jari-jari semakin bertambah besar. Sedangkan dalam satu periode, dari kiri ke kanan jari-jari semakin pendek. 2. Dalam satu golongan dari atas ke bawah densitas semakin besar 3. Dalam satu golongan, dari atas ke bawah nilai energi ionisasi unsur golongan IIIB semakin menurun. 4. Dalam satu golongan, dari atas ke bawah elektronegatifitas semakin kecil.

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5. Unsur

golongan

IIIB

terdiri

dari

:

Skandium

(Sc), yitrium

(Itrium), lanthanum, dan Aktinium. 6. Unsur golongan III B adalah golongan unsur yang memiliki kemiripan sifat paling dekat dengan unsur golongan II A. 7. Kelimpahan unsur golongan III B di muka bumi cukup jarang. II. Saran Demikian makalah tentang unsur golongan III B. Semoga bermanfaat dan selanjutnya dalam penyusunan makalah sejenis diharapkan penulis dapat menampilkan materi yang lebih lengkap.

DAFTAR PUSTAKA Anonim.

2009.

Golongan

IIIB.

(Online).

(http://kimiadahsyat.blogspot.com/2009/06/golongan-iii-b.html). Diakses pada: 05 Oktober 2014 Anonim.

2013.

Sistem

Periodik

Unsur

(SPU).

(online).

(http://kimlemoet.wordpress.com/2013/08/15/sistem-periodik-unsurspu/). Diakses pada: 05 Oktober 2014

23

Anwar,

Kay.

2013.

Lantanida.

(online).

(http://kanwar03oke.blogspot.com/2013/06/lantanida.html).

Diakses

pada: 05 Oktober 2014 Suciasih,

Rizki.

2014.

Golongan

III

B.

(online).

(http://rizkisuciasih.wordpress.com/2014/05/10/golongan-iii-b/). Diakses pada: 05 Oktober 2014 Utami,

Budi.

2012.

Sistem

periodic

Modern.

(online).

(https://www.academia.edu/5684762/Sistem_periodik_modern). Diakses pada: 05 Oktober 2014

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