The Extraordinary Properties of Ordinary Solutions by Yurii Fialkov

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From Raoult's law we can establish quantitatively how the boiling point of a solution depends on its concentration. Since each solution boils at a temperature of its own, it's convenient to relate concentration not to the boiling point itself, but to the amount by which it is elevated above the boiling point of the solvent. Mathematically, we can write that the boiling point of a solution is equal to Tb + ATb, where Tb is the boiling point of the solvent, and ATb is the boiling-point elevation of the solution.

Pressure in Solutions. The theory of solutions has unraveled all of the above findings, so important and so essential for chemists, from purely physical considerations. This is not the first and not the last case where physics comes out to help chemistry. That will be clear from the story about osmotic pressure that follows. Just to be sure I'll repeat what the reader undoubtedly knows well enough. 4 litres 46 capacity holds one mole of gas at a temperature of 273 kelvins (which is zero degrees on the Celsius scale), the gas exerts a pressure of one atmosphere.

Is it much or little? Well, it depends. Look at Fig. 13. What is it? An experiment on the Magdeburg hemispheres with the use of modern machines? No. In this imaginary experiment, 20 cars are trying to pull apart the cations and anions in one grammolecule of common salt, and it takes them a great deal to perform the act. But what would need the power packed in twenty modern cars and involve the risk of ruining their engines (of course, this "experiment" is only a literary turn) can readily be done by simply adding a glass of water.