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Transcript of crystals
CHEMICAL CRYSTALS CHEMICAL CRYSTALS RELATED TO LIFERELATED TO LIFE
Presented byPresented by
ANJALI.REJIV.ANJALI.REJIV.
CLASS-XICLASS-XI
IntroductionIntroduction
• Crystals are solids that form by a regular repeated pattern of molecules connecting together .
• In crystals, a collections of atoms called the Unit Cell is repeated in exactly the same arrangement over and over throughout the entire material.
• Naturally Crystals can take on strange and interesting looking forms because of the repetitive nature.
CRYSTAL SYSTEMCRYSTAL SYSTEM
• Triclinic crystal systems :Usually not symmetrical from one side to the other, which can lead to some fairly strange shapes
• Monoclinic crystal systems: Skewed tetragonal crystals, often forming prisms and double pyramids
• Orthorhombic crystal systems: Tetragonal crystals except not square in cross section (when viewing the crystal on end), forming rhombic prisms or dipyramids (two pyramids stuck together)
• Tetragonal crystal systems:Similar to cubic crystals, but longer along one axis than the other, forming double pyramids and prisms
• Trigonal crystal systems: Possess a single 3-fold axis of rotation instead of the 6-fold axis of the hexagonal division
• Hexagonal crystal systems: Six-sided prisms. When you look at the crystal on-end, the cross section is a hexagon
Cubic crystal systems: Not always cube shaped! You'll also find octahedrons (eight faces) and dodecahedrons (10 faces).
Physical/Chemical Physical/Chemical CClassificationlassification
• Covalent Crystals: has real chemical covalent between all of the atoms in the crystal-a single crystal of a covalent crystals - just one big molecule. Eg: diamond or zinc sulfide-extremely high melting points
• Metallic Crystals: Individual metal atoms sit on lattice sites while the outer electrons from these atoms are able to flow freely around the lattice. Metallic crystals normally have high melting points and densities.
• Ionic Crystals: A crystal where the individual atoms don't have covalent bonds between them, but are held together by electrostatic forces. Eg:- sodium chloride (NaCl). Ionic crystals are hard and have relatively high melting points.
• Molecular Crystals: A crystal where there are recognizable molecules in the structure and is held together by non-covalent interactions like vander Waals forces or hydrogen bonding. Eg :- sugar. Molecular crystals tend to be soft and have lower melting points.
SODIUM CHLORIDESODIUM CHLORIDE
STRUCTURE OF SODIUM STRUCTURE OF SODIUM CHLORIDECHLORIDE
• NaCl have an ionic structure• NaCl comes under cubic crystal
systems• It is hard ,normally white in color
USES OF NaClUSES OF NaCl
• Flavouring and preserving of food• Natural development of colour in ham• Carrier of Iodine• To produce other chemicals (chlorine and
sodium hydroxide)• Used in metal cleaners, plastics, water
treatment• For metallurgy and photography• To melt ice• Regulation of body fluids, medicine for
livestock and natural gas
DIAMOND CRYSTALSDIAMOND CRYSTALS
STRUCTURE OFSTRUCTURE OF DIAMOND CRYSTALSDIAMOND CRYSTALS
• The crystal structure of a diamond is a face cubic
• Diamond crystals can also form cubes, dodecahedra, and combinations of these shapes
• Real diamond crystals don't have completely smooth faces
USES OF USES OF DIAMOND CRYSTALSDIAMOND CRYSTALS
• Diamonds are an ideal of mechanical parts
• Diamond bearing are used in instruments for laboratories
• Diamond cutting tools cut much faster and accurately
SUGAR CRYSTALSSUGAR CRYSTALS
• Sugar is an informal term for class of edible crystalline substances, mainly sucrose, lactose, and fructose
• They are characteristically have a sweet flavour.
• It is an example for molecular crystals
Structure of sugar crystalStructure of sugar crystal
USES OF SUGARUSES OF SUGAR
• Ingredient in recipes and food preparation
• Glass-like material is made from crystals formed from sugar
• Sugar crystals are useful for organic synthesis and are used in the pigment, agriculture, plating and chemical sectors
• Used for lightening spots on skin
BLUEVITRIOL CRYSTALSBLUEVITRIOL CRYSTALS
STRUCTURE OF BLUEVITRIOLSTRUCTURE OF BLUEVITRIOL
• Copper(II) sulfate is the chemical compoundwith the formula CuSO4
• Encountered salt, is bright blue in color
• Archaic names for copper(II) sulfate are "blue vitriol" and "bluestone".[1]
• It has a triclinic structure
USES OF BLUEVITRIOLUSES OF BLUEVITRIOL
• As a herbicide, fungicide and pesticide
• As an Analytical reagent • For Organic synthesis • Used to grow crystals in schools
and in copper plating experiments
ICE CRYSTALSICE CRYSTALS
STRUCTURE OF ICE STRUCTURE OF ICE CRYSTALSCRYSTALS
• Ice crystals are a small crystalline form of ice including hexagonal columns, hexagonal plates,dendritic, crystals and diamond dust.
• Temperature and water vapour humidity determine crystalline forms.
USES ICE CRYSTALSUSES ICE CRYSTALS• Ice crystals are used for the freezing
process • Ice crystals are used for the pickling
of meat,vegetables,and fruits• Ice cream is a product .• Ice crystals are used for the
preservation of different substances
CONCLUSIONCONCLUSION
• We use many types of crystals in our daily life.They are having a wide range of classification.they are both interesting and attracting..They occur naturally and can be defined as a gift of nature.
REFERENCESREFERENCES
• NCRT text book for class +1.• Britannica Encyclopedia volume 3, 7,
5.• Yahoo search on different topics like:• Crystals and their uses• Types of crystals• Crystals of sugar,sodium
chloride,diamond,blue vitriol etc.