Thursday, October 10, 2019

Crystals Research Paper Essay

Crystals form in the depths of the Earth to the extension of the clouds in sky. Some think that crystals elude the sight of people’s eyes everyday in life, but they are everywhere including ingredients for food, construction materials, and even in ice-cold weather. The crystals in this experiment are ammonia-generated crystals that can be created right in a home. The experiment will be testing the different effects and products on crystals in different temperatures and forms of light. Different measurements will be recorded throughout the experiment such as mass and length. But first the crystals must grow. The scientific study of crystals and crystal formation is called crystallography. All over the world, though the different ages of man, crystals have been found to take their place throughout different cultures, countries, and religions. Not only were crystals used for a part in the currency of some ancient economies, but also they date back as far as 1500 BC as a source of healing and medicinal uses. â€Å"The ancient Egyptians strongly believed in the healing and protective power of crystals. Many pharaohs wore crystals on their headdresses and many crystal amulets have been found in their tombs.† Pharaohs of ancient Egypt often believed that the use of crystals in the masks and jewelry gave them the effect of bettering their rule. Amazonite and Lapis were reoccurring crystals found in the tombs found in Egypt, particularly King Tut where Lapis was actually apiece in the famous mask he wore. Cleopatra’s favorite jewelry was supposed to be a ring made of the crystal am ethyst. The ancient Chinese are also found to be users of the healing purposes of crystals. In two hundred different occasions, crystals are referred to in the bible. New Jerusalem, God’s heavenly city, was said to be built on top of crystals. â€Å"And the building of the wall of it was of jasper: and the city was pure gold, like unto clear glass. And the foundations of the wall of the city were garnished with all manner of precious stones. The first foundation was jasper; the second, sapphire; the third, a chalcedony; the fourth, an emerald; The fifth, sardonyx; the sixth, sardius; the seventh, chrysolite; the eighth, beryl; the ninth, a topaz; the tenth, a chrysoprasus; the eleventh, a jacinth; the twelfth, an amethyst.† Tibetan monks also viewed quartz crystal spheres as holy objects and worshiped them. The monks often referred to quartz as the â€Å"crystal of enlightenment†. Alexander The Great included a large emerald crystal encrusted in his battle helmet to insure a victory in the battle. The Shah Jahan, monks who built the Taj Mahal, wore talismans similar to Alexander The Great. Overall, There is a reoccurrence of crystals used for different purposes such as healing, sacred items, and fine jewelry. There are many different structures of crystals based on the formation of them. The different forms are Cubic, Isometric, Tetragonal, Orthorhombic, Hexagonal, Trigonal, Triclinic, and Monoclinic. Cubic and Isometric are similar but don’t always have to be cubes. They can be found in forms of octahedrons and dodecahedrons as well as cubes. Tetragonal form double prisms and double pyramids due to one axis being longer than the other. Orthorhombic form dipyramids and rhombic prisms. Hexagonal are six-sided prisms and when viewed from a certain angle, the cross section is a hexagon. Trigonal, instead of having a 6-fold axis like the hexagonal, it has a 3-fold, thus making it trigonal. Triclinic has no set shape so these kinds of crystals can come in any shape and strange ones as well. Monoclinic are very similar to tetragonal crystals except they are skewed a bit so they don’t form good angles. These formations of the atoms and molecules in a crystal are all part of what is called the crystal lattice. The crystal lattice is the repetition of a pattern in three dimensions. The atoms and molecules of crystals form in such a way that in all three dimensions, they are repeating a certain pattern. The shapes of the microscopic atoms can determine the shape of the macroscopic crystal. So, Cubic, Isometric, Tetragonal, Orthorhombic, Hexagonal, Trigonal, Triclinic, and Monoclinic atom formations repeat in different crystals to make them the shape they are. Crystals can also be grouped by their properties. The property arrangements include covalent, metallic, ionic, and molecular crystals. Covalent crystals have many true covalent bonds connecting all the atoms in the crystal. Covalent crystals tend to have very high melting points. Some covalent crystals include zinc sulfide and diamonds. Metallic crystal’s atoms sit on a lattice, therefore the outer electrons of the atoms in the crystal are free to move around and float whichever way they want. Metallic crystals have a high melting point like covalent crystals but just not as high. Ionic crystals are bonded together by ionic bonds just as covalent crystals are held together by covalent bonds. Ionic crystals have high melting points like the other crystals and are usually very hard. An example of an ionic crystal is salt (NaCl). Molecular crystals are very recognizable in terms of their molecular structure. They are bonding by hydrogen bonds or non-covalent bonding. Molecular crystals are usually soft and have lower melting points compared to the other crystals. Relating the properties of crystals to the atom structure (crystal lattice) will allow one to realize how the structure correlates to the property. They’re ere 2 different types of structure in the crystal lattice, crystalline and non-crystalline. Crystalline structures are the atom structures that contain the repeating patterns. While non-crystalline structures contain miniscule faults in the patterns and are not perfect. Ionic crystals contain a crystalline structure and therefore are very hard and dense. The more crystalline the structure, the more compact the atoms are arranged. And the more the compact the atoms are, the more dense and hard the crystal becomes. Molecular crystals tend to have a weak, non-crystalline structure of the atoms. This results in the Molecular crystals being weak with low boiling points. The atoms in Molecular crystal tend to be spread out over farther distances in contrast to ionic crystal’s structure. Different wavelengths and colors of light can affect the color of the crystal itself and the wavelength output of the crystal. Different crystals are different colors due to the different chemicals in each one and how each one absorbs light. Many crystals reflect a certain color of light depending on the chemicals. So, crystals absorb one color of light or wavelength of light, and reflect a different color of light. So the idea of complimentary colors comes into play. Complimentary colors are the colors that the crystals absorb to then reflect a different color of light. There are many examples such as if a crystal is yellow, it is reflecting yellow light but the light it absorbs is blue. Also, if a crystal is red, it is reflecting red light but it is absorbing green light. Normally, crystals will grow much faster in the light, but these crystals will be much weaker than crystals grown in the dark. This is due to the time it takes for each to grow. In dark rooms crystals grow at a much slower rate but are significantly stronger than crystals grown in light. Crystals are found all over and all inside the Earth. In some rock cavities, whether it is close to the surface or deep and closer to the core of the Earth, mineral-rich solutions contain the essential elements to grow crystals. Thus, in these rock cavities, many different crystals can be found, and some are very old. Crystals can also be found around volcanoes and past eruption areas because after a volcano erupts, the cooled magma forms crystals. In many caves, rock walls contain similar solutions as rock cavities and form similar crystals. Crystals can also be found where there are mineral-rich vapors present, such as deep caves and rock formations. Many different crystals can form in various environments. Such as the location of turbulent water such as pipes and quick paced streams. Also, crystals can be found in the presence of evaporating salt water, where salt crystals will form. Crystals are also formed in the process of condensation, or in clouds for that matter. Every time it snows, the water has frozen into microscopic ice crystals that are the snowflakes. Also, Crystals can form under water and many on the Earth have not been seen because of this. Crystals grow and form in different and various ways. Crystals begin growing in a process called nucleation, which contains 2 different types, unassisted and assisted. Unassisted nucleation occurs when a â€Å"proto-crystal† forms in the solution that has been added to a solute. The solute is the solid and the solution is the liquid surrounding the solute. When molecules in the solution begin to attract to one another they combine and sometimes are separated by intermolecular forces but sometimes they stay together. When these molecules stay together they begin to attract different molecules of the solution to join and this is the â€Å"proto-crystal†. The â€Å"proto-crystal† then attaches itself to a couple other molecules or other â€Å"proto-crystals† in the solution and the actual crystal begins to form. In assisted nucleation, the solution is provided with a solute that the molecules of the solution can attach or adsorb to. When this occurs it attracts molecules just as in unassisted nucleation and the crystals begin to form. Because of the ability for crystals to grow from the build up of the solute molecules in the solution, crystals are able to grow at their highest when the solution being used is saturated with the solute being use. The more material to build up, the more the crystals are going to be able to grow and grow to full extent. Crystal formation is very slow, so it must be given a long geological process to form. Depending on the kind of crystal, the times of formation vary, so some form faster than others. This is where super saturation comes into play. Super saturation is the presence of more dissolved material in the solvent that could be dissolved in normal conditions. When a solution is supersaturated, it contains many particles and molecules of material to begin the nucleation process. When the supersaturated solution is under the correct conditions, crystallization begins to occur more rapidly. But this is not the case for all liquids or solutions. Some solutions may be saturated at one temperature but supersaturated at another so temperature is able to affect this as well. Temperature plays a huge part in the growth and the rate in which crystals grow. The growth rate of crystals changes depending on the temperature they are in. But some crystals grow faster in warm temperatures than in cold temperatures. This is because of the process of evaporation. When a saturated solution is in a warm environment it begins to evaporate. When the liquid begins to evaporate, overtime the material that was once dissolved in the solution will begin to bunch up and crystallize the more the liquid evaporates. But this process is a lot quicker than in cold environments so this leads to less stability and weaker crystal strength. In colder environments, the opposite process is used to begin the crystallization process. The process of precipitation is used. This process takes a much longer time than the evaporation process. Since this process takes a much longer time, it has the ability to create well formed and high quality crystals that are much stronger than crystals formed in hotter temperatures. Mainly crystals grown in the dark take much longer to grow. Because of the absence of light, there is not as much heat than crystals in light. Crystals in light receive much more heat. But this is not the case for all types of crystals; in some cases the rules for temperature are switched. For example Borax, these are crystals that usually generate faster in colder temperatures. If the Borax solution is saturated at room temperature or at any temperature higher than room temperature, the crystals grow faster in colder temperatures. This is due to the molecular structure of the Borax solution and the movement of the molecules causes the saturated solution at room temperature to become a supersaturated solution at colder temperatures. And the super saturation leads to faster crystal growth. So growth rates vary depending on temperature, kind of crystal, and kind of solution being used in the experiment. Bibliography 1.†Crystal.† Wikipedia. Wikimedia Foundation, 13 Dec. 2012. Web. 15 Dec. 2012. 2.†History of Crystals.† History of Crystals. N.p., n.d. Web. 15 Dec. 2012. 3. â€Å"A Brief History of Crystals and Healing.† History of Crystals and Healing. N.p., n.d. Web. 15 Dec. 2012. 4.†Basic History of Crystals.† Holistic Apothecary. N.p., n.d. Web. 15 Dec. 2012. 5.†Types Of Crystals.† About.com Chemistry. N.p., n.d. Web. 15 Dec. 2012. 6.†The Structure of Crystals.† The Structure of Crystals. N.p., n.d. Web. 15 Dec. 2012. 7.ScienceDaily. ScienceDaily, n.d. Web. 15 Dec. 2012. 8.†Temperature and Crystal Growth.† Temperature and Crystal Growth. N.p., n.d. Web. 15 Dec. 2012. 9.†UCSB Science Line Sqtest.† UCSB Science Line Sqtest. N.p., n.d. Web. 15 Dec. 2012.

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