Transition Metals - Essay Example

Introduction The metals between the group 2 and group 3 are metallic events that are less reactive than group 1 and group 2 (Marshall Cavendish Corporation ,2003).The oxides and hydroxide are insoluble and these metals are called transition metals.Transistion metals are hard and dense and they are good conductors of heat and electricity.Transistion metals have higher melting points, boiling points and that is higher when compared with Group 1 and Group 2.The transition metals Iron, Cobalt and Nickel are strongly magnetic and transition metals are weakly magnetic.Transistion metals are very less reactive than Group 1 and Group 2.Trnsistion metals are extracted from their ores by chemical reducing agents. Iron Oxide is reduced to Iron by carbon monoxide. Zinc Oxide is also reduced by carbon to form zinc. The valence of transition metals are having more valency.Transition metals have colored ions except Zinc.Transistion metals have been acting as a catalyst and Iron and Iron oxide are used in Haber process. (complex metal ions) Transition metals is one which forms one or more stable ion and that have incompletely filled d orbitals. Some Specialty of Transition metals Iron has been used for steel(Chemistry). Copper for wiring and pipe. Titanium for paint Silver for photography paper US imports strategic minerals. Iron is used for storing and transport of oxygen. Catalyst nitrogen fixation Zinc has been found in 150 molecules Copper and Iron has been found useful for respiratory cycle. Cobalt has been found in Vitamin B12 Transition metals similarities have been found to occur in a period and within a group and that have been because of the last electrons being d group. D and f electrons cannot easily participate in the case of bonding and they are not affected by increased number of d electron. Transition metal ion can absorb light that is visible. Transition metals has melting points like W-3400 degree Celsius to hg,a liquid that has melting point at 25 degree Celsius. Iron and titanium has been found to be hard while copper, gold and silver has been found to be soft. The chemical reactivity will react with oxygen very well. The transition metal has been found to be protecting the metal from corrosion. Transition metal has different oxidation state like +2 and +3 level. Transition metal is surrounded by ligand. Transition metal has been found to be absorbing light that is visible. Transition metal ions are formed by losing from the 4s orbit and then from 3d orbit. The period is +2 is the common oxidation state and the nuclear charge increases and the d electron charge become lower in energy. Transitional metal can act as reducing agent and reducing will decrease going across the period. The radius of the transitional metal will be increasing from 3s to 4 D. Zr and ZrO2 has been found to be offering high resistance to high temperature and that has been used in making space vehicle. Niobium has been found to be alloying material for steel. Tantalum that has the ability to resist attack by body fluid can be used for replacement for bones (Ann Fullick,2001). The platinum group has been used as catalyst Transition metals have been found to be having two combining factors. The ability to form ionic bond with opposite charged ions. The ability to bid ligand to form complex ions. The primary valence can be said as the oxidation state and secondary valence as coordination number. The most common coordination number is 6 .Transitional metals have have more than one coordination number. Ligand can be a neutral molecule having alone electron pair and that can be used to form a band with metal ion. Ligand can form bond with a single ion or with two ion.Ligand can be used as a scavenger to remove the toxic heavy metals like lead from the body.Ligand has been found in many consumer products. The ligand is placed after the metal ion. The ligands are considered as negative charges.The ligand has the ability to produce d-orbital splitting. Properties of Transition Metals Transition metals do not react easily with oxygen and water and that means they corrode very easily. Transition metals are very good conductors of electricity and heat. Transition metals are very strong but can be bend to many shapes. Transition metals have high melting points and show less variation. Transition metals are very structural and can be mixed together like Bronze which is copper and tin.Cupro-nickel is copper and nickel. That has been used for making coins in currency. Iron is used widely in the construction of building and vehicles. Copper which is an excellent conductor of heat and electricity has been used for making wires. This is used for making electrical cables and high quality cookware. Copper had replaced lead in water pipes. Transition metals have the ability to form colored compounds. (complex metal ions) Transistion metals are forming various colors due to difference in oxidation levels. These colors are due to absorption of specific wavelengths of light as electron are found to be moving from lower to higher energy states. Potassium manganate is purple. The purple color is caused by the manganese ion in the compound. Copper sulphate is blue due to presence of the copper ion. Potassium chromate is orange due to the presence of chromium ion. The color of many metals, minerals, rocks and gem are caused by transition metal ions. A reddish brown color in rocks is due to presence of Iron ions. The blue color of sapphires and green color of gems is due to the presence of transition metal ions inside the compound. The glazes that are applied to pottery are due to transition metal ions. The green film for copper carbonate is due to copper. This green patina is very attractive and this is known as verdigris and this is the reason for using copper in many states. The color of one impurity can be counterattacked by another impurity. A yellow tint that is caused by iron impurity can be counteracted by adding neodymium. When transition metals form compound they are represented by Roman letter or number as well as having the name of compound Potassium Manganate (VII).Copper (II) Sulphate. This is due to the fact that transition metals have more than one ions. Different ions have the ability to cause different colors in the compounds. Iron(II) ions (Fe2+) give compounds with a green color and Iron (III)ions are usually reddish brown in color that is associated with rust. Iron a typical transition metal It has relatively two stable oxidation states in its compounds in the form of +2 and +3(Graham Hill, John Stranger Holman,2000). A variety of complex ions are formed. Iron has different colored compounds like pale green for Iron(II) and yellow or brown iron(III)salts. Iron is having important catalytic properties in the form of catalyzing the synthesis of Iron of Ammonia in Haber process. Iron has been used as pyrite, siderite, hematite and magnetite. Iron has been concentrated from iron ores. The separation has been done by magnets. The irons that are not magnetic are separated using floatation process. Iron can be used to reduce the carbon dioxide or CO2.The excess carbon dioxide will be removed by coke. Variable oxidation state in Copper. The same oxidation states of copper keep some mollusucs and Crustacean alive. Oxygen is not transported by hemoglobin as in humans and haemocyanin a blue substance that contains copper. Copper is an important industrial catalyst (George Burton,2000). Copper has been found to be producing two different colors and in Egyptian glass. A turquoise blue color when the cupric ion is present. A dull red color is present when cuprous ion is present. Copper in opaque reddish brown glass is used for decoration of Egyptian glass vessel. Metals have been seen as reflecting all the light energy coming to them but it has not been the case with copper. Copper has been seen as absorbing apart of spectrum. Copper has been seen as absorbing the blue and green light. Copper sulphate has been seen to blue color due to light energy being used to promote electrons in an atom that is combined with sulphate or carbonate ions. That means if white light in the form of sunlight is passed through copper sulphate solution, some wavelengths are absorbed by the solution. Copper (II) ions in the solution absorb light from the red region of the spectrum. The light which is passing through the solution and the colors that have passed through pale blue (Cyan). Convenient catalyst The chemical reactions have been seen as taking place very slowly. Most of the chemical reactions taking place in the chemical industries are very slow and that can lead to a situation of companies running in loss. That is when the reactions can be speeded up. That is the function of catalyst. The chemical reaction gets speeded up when catalyst works.Platinium and nickel are important catalyst in the process and vegetable oils like olive oil and corn oil are turned into margarine. Manganese (IV) oxide is a catalyst that is used in the decompositions of hydrogen peroxide.Platinium is the catalytic convertor that is attached to car engines. The catalytic convertor removes most of the pollutant gas produced by engine of car and it burns petrol before it reaches the atmosphere and it helps to combat pollution. Many transition metals share the same oxidation levels and as the oxidation state of the metal increases and that means splitting of the d orbitals.The change in the oxidation state can create a situation in which the color of light absorbed and color of the light that we see. That means changing oxidation state from +2 to +3. (complex metal ions) The 2+ ion is almost the same color as the hexaaquacopper (II) ion. The 3+ ion is the hard-to-describe violet-blue-grey color. The variable oxidation states of the transition metals and that makes hem useful for oxidation and reduction catalysts. It has been the case of air oxidation of sulphur dioxide in the presence of vanadium pentoxide.That has been the key stage in production of sulphuric acid. The ability of iron to produce loose complex with oxygen molecules helps it in hemoglobin and that helps to carry oxygen very far. Transition metals have the ability to form bonds with the electron pairs and form bonds with organic materials.In some rare cases the oxidation no of transistion metal is found to be zero. Vanadium ammonium vanadate(V) added to hydrochloric acid which is diluted , the formation is dioxovanadium(V) ion .That means white color gets changed to orange color.If granulated zinc I added then the color changes. oxidation state , ion , colour +4 , [VO(H2O)5]2+ , blue +3 , [VCl2(H2O)4]+ , green +2 , [V(H2O)6]2+ , violet Conclusion Transitional metal has been found to be advantageous and oxidation state and ligand has been found to be important in determine the nature of transitional metal. Reference “Chemistry”,viewed on June 8,2009,retrieved from http://www.authorstream.com/Presentation/bruce-37367-transmet-Transition-Metals-Coordination-Chemistry-Importance-Living-Organisms-survey-Metal-as-Education-ppt-powerpoint/ “complex metal ions”,viewed on june 8,2009,retrieved from http://www.chemguide.co.uk/inorganic/complexions/colour.html Graham Hill, John Stranger Holman,2000,"Metals and activity Iron",Chemistry in context ,pp.265 Marshall Cavendish Corporation ,2003,"Introduction of transistion metals",How It Works , Page 2488 George Burton,2000,"Copper",Chemical storylines ,pp.60. Ann Fullick,2001,"Transistional metals",Chemistry for AQA,pp.100-105. Read More