Introduction
The freezing point is a colligative property means that the extent of change depends on the freezing point only on the number of particles dissolved in solution. The freezing point, no matter what the particles, it is only those who are interested there. For this reason, the measurement of the change of the freezing point of pure solvent and a solvent with a known amount of substance there is a precise and absoluteValue of the number of molecules dissolved in solution. Knowing the mass of the dissolved and the freezing point of pure solvent provides enough information to accurately calculate the mass of the molecules without recourse.
Discussion
Each has its own and the freezing point of the solvent constant at its freezing molars -. The constant is the molar freezing point depression in degrees Celsius of the solvent to 1 mol of solute in 1 kg of dissolutionSolvents Ready (Chemical Technician's Reference Handbook, p. 435). Freezing point constants are published values for most of the pure solvent.
Many people, including me back if you are freezing the hard way. By this I mean that we have done our own equipment, test tubes, glass thermometers, a piece of wire and a bath of acetone dry ice. We continued our sample into the tube sticking the thermometer dipped wire then a bow around her like a handle, and thenthe solution frozen in dry ice-acetone. Once frozen, we moved our equipment and painstakenly traced the increase in temperature moves up and down the wire to keep the temperature constant. With this site, we estimated the freezing point as we could clean our equipment and went to the next sample. The process was slow, very funny, but inaccurate and not very convenient for a commercial laboratory.
Enter cryoscope, a tool that does all this automatically andon small samples of it. With microliter sample sizes up to a milliliter or so, a precise measurement of depression cryoscope freezing point of thousandths of a degree Celsius over a button at the bottom of the instrument calibrated. A single return value is the molecular weight easy to calculate. Hazardous solvents such as benzene, easily with a low risk of exposure analyst used.
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