Are the units to these answers supposed to be in L? Since the volume they give us is in liters, and when you use the equation
Minitial*Vinitial = Mfinal*Vfinal
the units you get for the final volume are liters, right?
Dilution module
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Re: Dilution module
Not necessarily. When you solve for the volume, you would get liters, but the options are in milliliters, so you need to convert your answer in L to mL.
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Re: Dilution module
Usually, dilution questions are completed in L, but they can also be done in mL as long as the units are consistent throughout. In this case, your answer would be in L, which you can then convert to mL since the answer choices are all in mL.
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Re: Dilution module
I think I remember Professor Lavelle saying something along the lines of "someone is more likely to say 'I need 6.36mL of solution' instead of 'I need 0.00636 L of solution." and that's why we usually convert to mL. It's not that big of a deal as long as you convert units correctly though.
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Re: Dilution module
Adding onto Nathan's point, dilution calculations' practical purpose is for use in the lab. Often, people are working with rather small volumes of liquids, so it's more practical to know the required volume in mL. There's no set rule that the answer has to be in mL or L, both are correct - the answer choices are usually in the units that make the most sense for the situation.
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Re: Dilution module
Usually you would compute the answer using L as units since that's the SI unit, but once you get the answer you can multiply it by 1000 if you want the answer in mL!
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Re: Dilution module
As stated above, typically you use the same units across the problem, but if the answer is in another unit, you can simply convert your answer! Also, out of practicality in labs, they may use mL instead of L if that seems more reasonable to use for the measurement.
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