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X-ray crystallography is the study of crystal structures through X-ray diffraction techneques. When an X-ray beam bombards a crystalline lattice in a given orientation, the beam is scattered in a definite manner characterrized by the atomic strucure of the lattice. This phenomenon, known as X-ray diffraction, occurs when the wave lenth of X-rays and the interratomic distances in the lattice have the same order of magnitude. In 1912, the German scientist Max von Laue predicted that crystals exhibit diffraction qualities. Concurretly, W. Fridrich and P. Knipping crated the first photographic diffraction patterns. A year later, Laurence Bragg successfully analyzed the crystalline structures of potassium chloride and sodium chloride using X-ray crystallography, and developed a rudimentary treatment for X-ray/crystal interaction (Bragg’s Law). Bragg;s research provided a method to determin a number of simple crystal strucures for the next 50 years. In the 1960s, the capabilities of X-ray crystallography were greatly improved by the incorporation of computer technology. Modern X-ray crystallography provides the most powerful and accurate method of determining single-crystal structures. Structures containing 100-200 atoms now can be anlyzed on the order of 1-2 days, whereas before the 1960s a 20-atom structure required 1-2 years for analysis. Through X-ray crystallography the chemical structure of thousands of organic, inorganic, organometallic, and biological compounds are determined every year.

Which of the following factors are consistant with the theory of X-ray crystallography?

X-ray crystallization causes a reduction in the ineratomic distance of wavelengths. X-ray are scattered according to the atomic structure of the srystal lattice. The analyasis of chemical compound was only possible after the development of computer technology. The process can be used to determin the chemical structure of biologicial compounds. X-rays will not defract in crystalline substances.
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