Laboratory report preparation equations

Most laboratories report results for the INR along with the patient s PT and the control value. The INR was devised as a way to standardize PT values and represents a way to correct the routine PT results from different laboratories using various sources of thromboplastin and methods of preparation for the test. The INR is determined by a mathematical equation comparing the patient s PT with the standardized PT value. Some institutions may use only PT, others PT/INR, and some may use INR. The INR is maintained between 2 and 3. 

Boron Trichloride. Boron trichloride is prepared commercially by the chlorination of boron carbide (equation 15). Direct chlorination of boric acid or a sodium borate in the presence of carbon is an alternative method. Most of the boron trichloride produced is converted to filaments of elemental boron by chemical vapor deposition (CVD) on tungsten wire in a hydrogen atmosphere. Numerous laboratory preparations of boron trichloride have been reported. One of the most convenient is the halogen exchange reaction of aluminum chloride with boron trifluoride or a metal fluoroborate. 

Although a chemical method for preparing diboron tetrachloride has been described, electric-discharge procedures still provide the most convenient route to this substance for the average laboratory worker. Stock used a discharge struck between zinc electrodes immersed in liquid boron trichloride to effect its reduction to diboron tetrachloride, but practically all preparative methods since reported have involved passing the trichloride, in the vapor phase, between mercury electrodes. The over-all process may be described by the equation ... 

Our laboratory has recently reported the preparation of a new series of polymers which undergo nucleophilic displacement reactions with catalysis by backbone functional groups (41-45). Equation 6 shows this catalysis in a schematic way. The consequences of this... 

This reaction used to be commonly employed in first-year chemistry laboratory exercises, but reports of isolated explosions have forced its elimination from such situations. Great care should be used in preparing oxygen in this manner. A safer method is to oxidize a mild solution of hydrogen peroxide with potassium permanganate in acid solution, as shown in Equation (11.3) ... 

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