Faulty logic Kaplan Question?

[El Curandero]

So in a physical science review question it gave us a passage telling us how low levels of H2O is very harmful. Here's the question: In cryonics, scientists are attempting to save lives by lowering patients body temperatures to 100 K. One hurdle being faced is that ice crystals can form and damage cells. This freezing and damaging could be alleviated by:

I chose lower pressure to prevent solids from forming but it showed the right answer as high solute levels to raise freezing point.

Okay, I know adding solutes increasing the freezing point but did you not just say lower concentrations of water, which is relative to solute concentration, will damage cells, which you are trying to avoid...and wouldn't lowering the pressure also avoid solids from forming without damaging cells?

Am I right or am I overanalyzing? Kaplan seems to be using faulty logic all the time for their conceptual questions.

El Curandero

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[ElectricNoogie]

My guess is you want to consider the T at which you are working (100 K, -173.15 C). At such a low temperature the water will be solid @ essentially all pressures, so adding solute is the best option to lower the freezing point and prevent cell damage.

Remember, BP elevation and FP depression go hand-in-hand when raising solute levels.

 

[RaspberrySlushy]

Adding solutes should lower the freezing point not increase it. But I think that's what they meant. If you add enough solutes you lower the freezing point and therefore avoid ice formation even at a low temp.