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Originally Posted by Slavakion
True or false? Adding salt to a pot of water makes it reach the boiling point faster. True
Erm, adding solutes does affect the boiling/freeezing point, but by making them higher/lower respectively. Which would technically make it reach the BP later, right?
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Right, adding salt increases boiling point, and ICER gives a good explanation.
However, the question is only talking about reaching the bp, not what the bp itself is. And I'd agree with you that with a higher bp, it would take a longer time to heat the water. Which then confuses me, because when cooking pasta, you sometimes add a pinch of salt, which people say makes the water boil faster. I think this is where this question comes from.
I've googled it, and one possible answer is that the salt provides nucleation sites for the water to start boiling, but this seems unlikely because salt is soluble in water, and you would need larger insoluble particles for nucleation sites. My only other guess is that the salt affects the specific heat but i don't know enough about those thermodynamics to say anything definite, and my instinct says that it can't affect it by much...