Each carbon atom is attached to four other carbon atoms 1. It is a strong, rigid three-dimensional structure that results in an infinite network of atoms. This accounts for diamond's hardness, extraordinary strength and durability and gives diamond a higher density than graphite 3.
Because of its tetrahedral structure, diamond also shows a great resistance to compression. The hardness of a crystal is measured on a scale, devised by Friederich Mohs, which ranks compounds according to their ability to scratch one another.
Diamond will scratch all other materials and is the hardest material known designated as 10 on the Mohs scale. It is the best conductor of heat that we know, conducting up to five times the amount that copper does. Diamond also conducts sound, but not electricity; it is an insulator, and its electrical resistance, optical transmissivity and chemical inertness are correspondingly remarkable. Moreover, diamonds disperse light. This means that the refractive indices for red and violet light are different 2.
As a result, the gemstone acts like a prism to separate white light into rainbow colors, and its dispersion is 0. The greater the dispersion, the better the spectrum of colors that is obtained. This property gives rise to the "fire" of diamonds. The "brilliance" of diamonds stems from a combination of refraction, internal reflection and dispersion of light.
For yellow light, for example, diamond has a high refractive index, 2. This means that when yellow light passes into a diamond and hits a second face internally at an angle greater than There is a rigid network of bonds within the diamond crystal. What is the bond length for a diamond C-C bond? Double click twice on first atom, drag to second atom and double click again.
Please enter your answer in the space provided: angstroms. Graphite is can be described as a hard and crystalline b soft and slippery c a dark liquid d made only of carbon and hydrogen atoms. Diamond is a made only of carbon and hydrogen atoms b the hardest substance know to man c soft and slippery d clear and brittle 3. What makes diamond so hard? Which statement best describes why graphite is soft? Which of the following statements is not correct a both carbon and diamond are made of only carbon atoms b graphite has only weak forces between its layers c graphite and diamond have the same density d in diamond each carbon is the same distance to each of its neighboring carbon atoms More Molecules.
Multiple Choice Questions 1. Questions or Comments? Try this: Rotate the Graphite molecule Hold the left mouse button down over the image and move the mouse to rotate the graphite molecule. Very strong silicon-oxygen covalent bonds have to be broken throughout the structure before melting occurs. Morevoer, it hard due to the need to break the very strong covalent bonds. Silicon Dioxide does not conduct electricity since there aren't any delocalized electrons with all the electrons are held tightly between the atoms, and are not free to move.
Silicon Dioxide is insoluble in water and organic solvents. There are no possible attractions which could occur between solvent molecules and the silicon or oxygen atoms which could overcome the covalent bonds in the giant structure.
Jim Clark Chemguide. The allotropes of carbon have been covered in sufficient detail in Chapter 8. Skip this long section!
Ionic carbides are formed by elements of groups 1, 2 and aluminum. The actual for of the carbon varies, for example, aluminum carbide, based on its hydrolysis product seems to contain "C 4- " units:.
Interstitial carbides are compounds of the transition metals with metallic properties and the C in tetrahedral holes in the metal atom lattice. The best known example is the extrememly hard tungsten carbide, WC, used in cutting tools. Covalent carbides include B 4 C 3 and SiC carborundum - an abrasive with a diamondlike structure.
Diamond Carbon has an electronic arrangement of 2,4. How to draw the structure of diamond Don't try to be too clever by trying to draw too much of the structure! Do it in the following stages: Practice until you can do a reasonable free-hand sketch in about 30 seconds. Very strong carbon-carbon covalent bonds have to be broken throughout the structure before melting occurs.
This is again due to the need to break very strong covalent bonds operating in 3-dimensions. All the electrons are held tightly between the atoms, and aren't free to move.
There are no possible attractions which could occur between solvent molecules and carbon atoms which could outweigh the attractions between the covalently bound carbon atoms. Graphite Graphite has a layer structure which is quite difficult to draw convincingly in three dimensions. The Bonding in Graphite Each carbon atom uses three of its electrons to form simple bonds to its three close neighbors.
Silicon dioxide: SiO 2 Silicon dioxide is also known as silica or silicon IV oxide has three different crystal forms. Contributors Jim Clark Chemguide. Introduction There are more compounds of carbon than of any other element except hydrogen.
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