introduction during the formation of the planet earth, there were elements which did not fit into the crystal structures of the minerals found in the mantle, instead they prefer to be in the liquid phase which would later form the crust. these elements were said to be incompatible in the mantle relative to the crust, hence the name incompatible elements. these elements include the alkali metals: K, Rb, Cs, the transitional elements: Y, Zr, Nb, Hf, Ta, the actinide: Th, U, and all the lanthanides. According to Goldschmidt, all of these elements combined are called the lithophile elements
CHEMISTRY
Alkali metals- K, Rb, Cs
These are the elements which are found in the first raw of the periodic table. They have a single electron in their outer shell which they will readily loose in an ionic bonding with other elements to form one positively charged ion or cation. Removal of this single electron gives these alkali metals an inert gas configuration that is stable as a result. They also have the ionization potentials which are very low in their respective periods. All of these metals are highly reactive, as a result, in nature they will rarely occur in elemental form. it is also because of this highly reactive nature, that when some of these elements are exposed in water, they explode. Alkali metals have a low melting point and low density. they are also soft and ductile, and also good conductors of electricity.
Rubidium
Rb is silvery white and occurs as a solid at room temperature. Its melting point is about 39˚c. its atomic number, with a density of 1533 kg.m.
Potassium
K with an atomic number of 19, also occurring as a solid at room temperature is so reactive that it will even react and burn a hole through ice
Ceicium
The wil...
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...readily combine with other ligands to form stable complexes. These elements are all unstable and very reactive due to atomic numbers above 83. Thorium and Uranium are the only actinides which occur naturally in the earth's crust.T
Thorium
With atomic number of 90, Th has a melting temperature of 1750˚C and a density of 11725 kg/m ᵌ.
Uranium
U is considered as the heaviest naturally occuring element, with a nucleus that draws its core electrons shells in closer to it because it is so full of protons and neutrons. This makes the relativistic effect to occur. This effect affects the electron orbital energies that the inner electrons will rotate in a fast manner towards th nucleaus to shield it better. As a result, the outer valence orbitals will be shielded and expanded, forming hybrid molecular orbitals.
Works Cited
www.rsc.org/periodic-table/element/39/yttrium
Strontium was discovered by Adair Crawford, an Irish chemist, in 1790 while studying the mineral witherite (BaCO3). When he mixed witherite with hydrochloric acid (HCl), he did not get the results he expected. He assumed that his sample of witherite was contaminated with an unknown mineral, a mineral he named strontianite (SrCO3). Strontium was first isolated by Sir Humphry Davy, an English chemist, in 1808 through the electrolysis of a mixture of strontium chloride (SrCl2) and mercuric oxide (HgO). Strontium reacts vigorously with water and quickly tarnishes in air, so it must be stored out of contact with air and water. Due to its extreme reactivity to air, this element always naturally occurs combined with other elements and compounds. Strontium is very
It has a molar volume of 9.38 ×10-6 m3/mol. Molybdenum has an atomic weight of 95.94 amu. Its atomic number is 42. The atomic radius is 145 pm and the covalent radius is 145 pm also. Its electron configuration is [Kr]4d^5 5s^1.
Aluminum is a lightweight, silvery metal. The atomic weight of aluminum is 26.9815; the element melts at 660° C (1220° F), boils at 2467° C (4473° F), and has a specific gravity of 2.7. Aluminum is a strongly electropositive metal and extremely reactive. In contact with air, aluminum rapidly becomes covered with a tough, transparent layer of aluminum oxide that resists further corrosive action. For this reason, materials made of aluminum do not tarnish or rust. The metal reduces many other metallic compounds to their base metals. For example, when thermite (a mixture of powdered iron oxide and aluminum) is heated, the aluminum rapidly removes the oxygen from the iron; the heat of the reaction is sufficient to melt the iron. This phenomenon is used in the thermite process for welding iron .
This element when becoming an isotope can become radioactive due to its high activity as a metal. In its natural state it is a soft metal and it has a shiny “ wax “ like silver/white color to it, it is so soft that a knife could cut through it without a problem.
-------------------------------------------------------------------- The reactivity series is a table to show which metals are most reactive to the least reactive. Potassium is known as the most reactive and platinum the least. --------------------------------------------------------------
I am going to discuss about the element known as gold in my assignment. To describe the element gold in simple terms, I can only say that it is an element (chemical element). This element is denoted by the symbol Au. It has an atomic number of seventy nine (79). I will describe quite a number of things concerning gold as an element. To begin with is:
Isotopes refer to 1 of 2 or more atoms with the same atomic number but different numbers of neutrons. The atom copper has two stable isotopes. They are 63Cu and 65Cu. 63Cu has an isotope atomic mass (in amu) of 62.9295989 and a natural abundance (in atom %) of 69.17. 65Cu has an isotope atomic mass (in amu) of 64.9277929 and a natural abundance (in atom %) of 30.83. The averag...
Melting Point Determination of Alum 1. 0.5 g of dry alum was crushed with the mortar and pestle, and then the crushed alum was packed to the bottom the capillary tube. The alum measured about 0.5 cm from the bottom of the tube. Then the tube was fastened to the thermometer with the rubber band, and the thermometer was fastened to the ring stand with the universal clamp. 2.
Potassium is a solid silvery white element. It is soft and can be cut with a knife. Potassium is the least dense known metal, besides lithium. It is the seventh most abundant element. It makes up about 1.5% by weight of the earth's crust. It decomposes in water because of the hydrogen. It usually catches fire during reaction with water.
As elements get heavier the ratio of neutrons:protons moves away from being 1:1, Bands of instability surround the band of stability showing where the neutron:proton ratios are either to great or too small,
The Periodic Table is based around the Atomic Theory. Firstly people believed that everything was made up the four elements Earth, Fire, Wind, and Water. This theory evolved into everything being made up of atoms. Breakthroughs throughout history such as the discoveries of the nucleus, protons, neutrons and electrons have pushed this theory forward to where it is today.
Uranium was discovered by Martin Heinrich Klaproth, a German chemist, in the mineral pitchblende (primarily a mix of uranium oxides) in 1789.Klaproth, as well as the rest of the scientific community, believed that the substance he extracted from pitchblende was pure uranium, it was actually uranium dioxide (UO2). After noticing that 'pure' uranium reacted oddly with uranium tetrachloride (UCl4), Radioactivity was first discovered in 1896 when Antoine Henri Becquerel, a French physicist, detected it from a sample of uranium. Today, uranium is obtained from uranium ores such as pitchblende, uraninite , carnotite and autunite as well as from phosphate rock , lignite (brown coal) and monazite sand . Since there is little demand for uranium metal, uranium is usually sold in the form of sodium diuranate , also known as yellow cake, or triuranium octoxide).
molecules its size it would have a boiling point of -75øC and a freezing point of -125øC4.
The Web. The Web. 28 Apr. 2014. The 'Standard' of the 'Standard'. Metal Melting 101 - How To.