Molarity unit  [ENDORSED]

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Daniel Rivas 3L
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Joined: Fri Sep 29, 2017 7:07 am

Molarity unit

Postby Daniel Rivas 3L » Fri Oct 06, 2017 12:43 am

So I was working on a lot of molarity questions recently and I was wondering. does Molarity always have the unit of mol/L? Or can it sometimes equal mol/ml if you keep it the same? or is it a different unit altogether? I'm just a little confused about it.

Nishma Chakraborty 1J
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Re: Molarity unit  [ENDORSED]

Postby Nishma Chakraborty 1J » Fri Oct 06, 2017 12:51 am

Hey! From by best understanding (and from what my teachers have done in the past), molarity has always been in the standard mol/L. Whenever a volume is given in ml, I convert it to L. Hope that helps!

Kevin Liu 3G
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Re: Molarity unit

Postby Kevin Liu 3G » Fri Oct 06, 2017 11:53 am

Yes, it is best to never do mol/ml because the formula always uses mol/L and it is the more accepted version. Besides, you wouldn't want the grade to mistakenly think that you wrote 13 L instead of 13 ml.

Ruohan Sun 3I
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Re: Molarity unit

Postby Ruohan Sun 3I » Sat Oct 07, 2017 4:34 pm

The mostly used unit M is mol/L, but you can also use other units such as mol/mL

SitharaMenon2B
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Re: Molarity unit

Postby SitharaMenon2B » Sat Oct 07, 2017 4:44 pm

Molarity as an SI unit is usually defined by moles per liter so I would say you probably should not use moles per mL

StephanieRusnak
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Re: Molarity unit

Postby StephanieRusnak » Sat Oct 07, 2017 7:30 pm

I would say always use mol/L for molarity, even if in certain calculations the L will cancel, I think its best to show your understanding of the definition of molarity.

804899546
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Re: Molarity unit

Postby 804899546 » Sat Oct 07, 2017 8:22 pm

What is the difference between molarity and molality?

Jesus Rodriguez 1J
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Re: Molarity unit

Postby Jesus Rodriguez 1J » Sat Oct 07, 2017 8:33 pm

The standard units for molarity are mol/L so I would suggest using those units. If a problem for some reason asks you for Molarity in terms of mol/ml you can always convert the Liters.

Gobinder Pandher 3J
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Re: Molarity unit

Postby Gobinder Pandher 3J » Sat Oct 07, 2017 11:30 pm

Molarity is defined as the moles of solute per liter of solution. I don't think you'll ever see molarity as moles/mL. I hope this helps.

Samira Tootla 1J
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Re: Molarity unit

Postby Samira Tootla 1J » Sat Oct 07, 2017 11:38 pm

Molarity is the number of moles of solutes per liter of solution, whereas molality is the number of moles of solute per kilogram of solvent. Molarity's SI unit is mol/liter and molality's SI unit is mol/kg. Hope that answered the questions above.

Samira Tootla 1J
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Joined: Fri Sep 29, 2017 7:04 am

Re: Molarity unit

Postby Samira Tootla 1J » Sat Oct 07, 2017 11:38 pm

Molarity is the number of moles of solutes per liter of solution, whereas molality is the number of moles of solute per kilogram of solvent. Molarity's SI unit is mol/liter and molality's SI unit is mol/kg. Hope that answered the questions above.

Amelia Georgius 1K
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Re: Molarity unit

Postby Amelia Georgius 1K » Sun Oct 08, 2017 9:16 pm

It is usually easiest to convert all of your units to SI units at the beginning of a problem so that you are less likely to make an error in the calculation and answer, which in this case the SI unit is mol/L.


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