Introduction to Thermodynamics - Two Basic Problems

AI Thread Summary
The discussion focuses on two thermodynamics homework problems involving boiling water and evaporation rates. The first problem requires calculating the time it takes for 1 liter of water to evaporate at a rate of 1g/min, with hints provided about the weight of water. The second problem involves deriving a mathematical relationship for salt concentration in a kettle with 20g of salt as water evaporates. Participants emphasize the importance of showing work rather than simply providing answers. The thread encourages collaborative learning while maintaining academic integrity.
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Homework Statement

1. A kettle holding 1 lt. of water is boiling. Assuming water is evaporating at a constant evaporation rate of 1g/min, determine how long it will take for the kettle to dry out.

2. Another kettle holding 1 lt. of water and 20g of salt is also boiling. Again water evaporates at a rate of 1g/min. This time you are asked to derive a mathematical relationship for how salt concentration in the kettle changes with respect to time.
 
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These are so easy that it's difficult to give you a hint without telling you the complete answer, but here's a try:

1. 1 liter weighs 1 kg.

2. The amount of water in the kettle (actually the weight in grams) after t seconds is 1000-t/60.
 
WELCOME TO pf .

Show some work before we take over ur problem.

We just help in your homework ..we don't solve it buddy.
 
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