Introduction This book report discusses the book which is called “Rare Earth: Why Complex Life is Uncommon in the Universe”, and written by Peter D. Ward and Donald Brownlee. The designated book is in the paperback edition published by Copernicus Books in New York in 2003. There are thirteen chapters in total. “Rare Earth: Why Complex Life is Uncommon in the Universe” is a book introducing and discussing the “Rare Earth Hypothesis”. The “Rare Earth hypothesis” argues that the occurrence and development of those complex multi-cellular lives including highly intelligent human beings on the earth, require an extremely uncommon combination of, diverse geological, biological, chemical, meteorological and astrophysical factors, events and circumstances.
There are 17 rare earth elements that are considered to be rear earth metals. They are Scandium and yttrium and the fifteen lanthanides. Scandium and yttrium are both transition metals and rare earth metals because they are usually found with the rare earth metal deposits. The rare earth elements contribute to technologies people rely on today. They make possible the high tech world we live in today.
The word "rare” can make you think that the world is lacking these elements but the elements are in fact relatively abundant in the Earth's crust but in limited, insufficient amounts. The rare earth elements group got their name because at their initial discovery only tiny pieces of these metals could be separated from greater quantities of more common elements. rare earth elements tend to be found in the same ore deposits. The Japanese call them “the seeds of
Trace metals those available in little quantity in environment. Trace metals in coastal environments, are resulting from three key sources (i) The contiguous watershed, (ii) The offshore marine environment, and (iii) Industrial and/or urban runoffs (Jones and Jordan, 1979). The Acid leachable trace metals are (Fe, Ni, Pb, Mn, Zn, Cu,Cr) the fraction easily available in the environment absorbed by biota. Metals which are representing the least mobile form they are entrapped in crystal structure of minerals in residual fraction (Miretzky et al. 2011).
Selenium - The Element In 1817, Jöns Jacob Berzelius found out an unknown substance with properties similar to that of tellurium and named it as Selenium, from the Greek word Selene, which denotes goddess of the moon1. Selenium is one of the rarest elements that are found naturally in the earth’s crust. It occupies group 16 (chalcogens) of the periodic table of elements with atomic number 34 and symbol Se. Selenium exists in multiple allotropic forms but only three are recognised. The most stable form is a metallic gray crystalline hexagonal selenium, second is crystalline monoclinic selenium which is deep red in colour and the third one is amorphous selenium, which appear red in powder form and black in vitreous form.
Amino acids with a polar R group are neutral and polar or hydrophilic. They are more soluble in water. Polar side chains can be uncharged or carry a negative or positive
The author of the “terraforming mars” doc writes “There is an abundance of rare metals on Mars such as platinum, gold, silver, and others. Shipping from Mars to Earth, as mentioned above, is much easier than the other way around.”. Mining materials from Mars will extend the limited amount of time humankind has to find alternative methods for daily life. Besides the materials residing in martian soil, Mars also is neighboring the asteroid belt, and the asteroids are composed of precious materials. The author of the “terraforming mars” doc writes “Even more promising is the proximity of the asteroid belt to Mars.
This is because silver ions form more stable complexes with NH3 than with water. Aldehydes will be oxidised to silver metal carboxylate ion and precipitated as "silver mirror" on the wall of the test tube. The diamminesilver ion was reduced to metal silver while the aldehyde in turn was oxidized to a carboxylic acid (gluconic acid). Ketones do not react with Tollens'
EXPERIMENTAL SECTION Materials Materials used for this study were AMD samples, NSW from natural sulfuric hot springs, K2Cr2O7 (0.25 N), sulfuric acid reagent (Ag2SO4, concentrated H2SO4), oxidizing/digesting solution (K2Cr2O7, concentrated H2SO4, HgSO4), standard solution of KHP/Potassium Hydrogen Phthalate (HOOCC6H4COOK), Ferro Ammonium sulphate (FAS) 0.1 N, Ferroin indicators, sulfuric acid (H2SO4), HCl 6, standard solution of Iodine (I2) 0.025 N, sodium thiosulfate solution (Na2S2O3) 0.025N, 2% Starch Indicator, Natrium sulphate (Na2SO4), BaCl2(s), a buffer solution, Ca(OH)2 0.1 M, HCl 0.1M and distilled water. Instrumentation The instruments used for this study were analytical balance, glassware, rubber bulb, pH meter, filter paper, thermometer,
Elements eighty nine to one hundred three are the actinides. Elements located here are not in columns, however, they are horizontal. The particular rare earth metals known as lanthanides are used in the lighting industry. Actinides are very unstable and they are all are radioactive. Actinides do not occur in nature.