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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: Zenzen on February 23, 2020, 03:48:20 PM

Title: mmol to grams
Post by: Zenzen on February 23, 2020, 03:48:20 PM
Hello, I am seeking to make a solution of 40 MMOL/L of butyrate, but I need a conversion to grams/L.

The molar mass of butyrate is 87.098 g mol−1 

https://en.m.wikipedia.org/wiki/Butyrate

Could someone please tell me how many grams per liter is 40 MMOL/L of butyrate?

I’m not a chemistry major so if someone could please help me I would really appreciate it!!!

P.S. I found this website with conversion information but I can’t make heads or tails of it...

https://sciencing.com/calculate-mmol-5144535.html
Title: Re: mmol to grams
Post by: chenbeier on February 23, 2020, 04:01:01 PM
40 mmol/ l = 0,04 mol/l

Mole = mass/molar mass

Mass = Mole x molar mass

Now you should be able to calculate it.

The molar mass what you had looked up ja for the anion. Which butyrate you have available?

Sodium, pottasium?

You have to add the molar mass of the metal as well.
Title: Re: mmol to grams
Post by: Zenzen on February 23, 2020, 04:32:26 PM
Hi chenbeier,

The bottle says the ingredient is butyric acid with sodium. 

Here is the label:

https://cdn.shopify.com/s/files/1/0217/3199/9816/products/sp990_bus60_labelno.-544.6_1800x1800_f17a7e08-2930-43fe-afc1-fc080ddd4526_1800x1800.png?v=1573082273

I looked the mmol of butyric acid is:  88.106 g·mol−1

I don't know how to calculate this, even with the the formula you've given...I'm not a chemistry major.  If you or someone could tell me how many grams of butyric acid = 40 mmol of butyric acid, it would be so greatly appreciated. 

Title: Re: mmol to grams
Post by: Zenzen on February 23, 2020, 04:37:05 PM
The capsule has 1.2 grams per capsule.  Just wanting to know how much of this capsule per liter of water to make 40 mmol per liter. 
Title: Re: mmol to grams
Post by: OrganicDan96 on February 23, 2020, 05:16:25 PM
it's probably sodium butyrate you can find out the molar mass of this
Title: Re: mmol to grams
Post by: chenbeier on February 23, 2020, 05:31:38 PM
It is the sodium salt, definitely.

So add molar mass of butyrate and molar mass of sodium.
Title: Re: mmol to grams
Post by: Zenzen on February 23, 2020, 06:01:32 PM
There are 1.2 g of bytyric acid in a capsule, and 313 mg chloride per capsule.   

Could someone please tell me how many MMOL of butyric acid = 1.2 grams of butyric acid?

The mmol of butyric acid is:  88.106 g/mol−1

I don’t know how to do this conversion, so any help on this calculation would be appreciated.

Title: Re: mmol to grams
Post by: Borek on February 23, 2020, 07:42:07 PM
I feel like you are not even trying.

Do you know what mili means?

You are told "40 mmol/L" - to prepare 1 L of the solution, how many mmoles do you need?

How many moles is that?

You are told mass of one mole of the butyric acid is 88.1 grams. What is mass of half a mole?

0.1 mole?

What is mass of number of moles that you need?

In how many capsules is that mass of butyric acid present?

Answer each question exactly in the order I asked and you will get the answer. And none of these questions is in any way specific to chemistry.
Title: Re: mmol to grams
Post by: Zenzen on February 24, 2020, 11:42:59 AM
Thank you so much for that reply. And for all of the replies above.

 I went through these questions you posed and actually that was very helpful. So these are my answers, could you please let me know if my calculations are correct?

A mili is 1/1000

40 mmol are needed per liter

.04 mol are needed per liter

The mass of one mole of butyric acid is 88.1 g.

the mass of half of a mole = 44.05 g

The mass of 0.1 mole = 8.81 g

The mass of 0.04 of a mole = 3.524 g

So 3.524 grams are needed per liter?

So that would be approximately 3 capsules per liter?






Title: Re: mmol to grams
Post by: Borek on February 24, 2020, 05:00:09 PM
So that would be approximately 3 capsules per liter?

Yes.