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Topic: Molarity and unit conversions.  (Read 2658 times)

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Offline confusedcollegestudent

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Molarity and unit conversions.
« on: July 10, 2017, 09:09:49 PM »
The problem says:
Calculate the number of moles of NaBH4 in 1.5 mL of NaBH4 solution, if there are 80 mg of NaBH4 per milliliter of solution used?
How would I start or set up this problem??

Offline XeLa.

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Re: Molarity and unit conversions.
« Reply #1 on: July 10, 2017, 09:19:07 PM »
Firstly, identify the meaning of molarity, and work from there.


Offline Babcock_Hall

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Re: Molarity and unit conversions.
« Reply #2 on: July 11, 2017, 10:29:21 AM »
What do you need to convert from mass (typically in grams) to amount (typically in moles), or vice versa?

Offline P

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Re: Molarity and unit conversions.
« Reply #3 on: July 12, 2017, 06:49:25 AM »
All good advice  -  you break it down to first principles...  count the atoms! :-)
Tonight I’m going to party like it’s on sale for $19.99!

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Offline CSteps

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Re: Molarity and unit conversions.
« Reply #4 on: August 27, 2017, 03:02:52 PM »
Convert the mg to g first. it is 0.08 g.

Then you can do it by the following conversion:

moles of NaBH4 = 1.5 mL x 0.08 g/1 mL x 1 mol NaBH4/37.8 g

In the first step, we find how many grams of NaBH4 we have and in the second, we convert it to the mass using the molar mass of NaBH4 which is 37.8 g/mol.

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