December 08, 2022, 05:01:49 PM
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### Topic: I need some advice about what is the right formula to use:  (Read 782 times)

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#### FeuersternWaCa

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##### I need some advice about what is the right formula to use:
« on: March 25, 2022, 05:42:08 AM »
I need to find mass concentration (c) and I have M, density (p) and mass fraction w (only in percentage).
The two formula I think I can use are:
$$c=\frac {w*p}M$$
or
$$c=\frac pM$$

« Last Edit: March 25, 2022, 06:43:13 AM by Borek »

#### Borek

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##### Re: I need some advice about what is the right formula to use:
« Reply #1 on: March 25, 2022, 06:42:56 AM »
Will it help to assume you have exactly 1000 g of the solution? What would the volume be? What would be mass of the solute?
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#### FeuersternWaCa

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##### Re: I need some advice about what is the right formula to use:
« Reply #2 on: March 25, 2022, 07:32:38 AM »
Will it help to assume you have exactly 1000 g of the solution? What would the volume be? What would be mass of the solute?
The only things I have are
$$p=1 \frac {kg}L$$
and
$$M=60 \frac {g}{mol}$$
and
w=0,1%

#### Borek

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##### Re: I need some advice about what is the right formula to use:
« Reply #3 on: March 25, 2022, 10:43:33 AM »
As I wrote: assume 1000g of solution. What volume does it have? (you know the density, it is a trivial application of the definition)

Finding mass of the solute is also a trivial application of the weight fraction definition.
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