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I need help to make the following chemicals. I cannot locate any recipes in any of my books

1) Fe(NO3) .....0.0020m

2)KSCN .........0.0020m

3)Fe(SCN)3 .......0.0002m

thanking you all in advance

Ferric nitrate may be available in nonahydrate or anydrous form. Check on the lable.

* Fe(NO3)3.9H2O is 403.999 g/mol so 0.0020M will be 0.0808 g/100mL
* Fe(NO3)3 is 241.86 g/mol so 0.0020M will be 0.0484 g/100mL

Potassium Thiocyanate

* KSCN is 97.181 g/mol so 0.0020M will be 0.0194 g/100mL

Ferric Thiocyanate complex forms in the colourimetric determination reaction. You don't make your own.

* Fe(NO3)3 + 3 KSCN = Fe(SCN)3 + 3 KNO3

Suggestion: For the calibration plot, 0.10 mL increments of 0.00100 M KSCN are added to 4.00 mL of 0.200 M Fe(NO3)3, and for the equilibrium solutions, 0.50 mL increments of 0.00200 M KSCN are added to 4.00 mL of 0.00200 M Fe(NO3)3.

Hi
I use a website called Mass Molarity Calculator Sigma-Aldrich for when I have hard solutions to make. https://www.sigmaaldrich.com/chemistry/ ... lator.html
I just click on one of the links to work things out.
Hope this helps

From the recipe section of Pearson Chem 12 to prepare 0.0002M iron(III) thiocyanate

pipette 10ml 0.002M KSCN into a 100ml volumetric flask
make up to 100ml with 0.002M Fe(NO3)3
make fresh as solution degrades

This new year 12 Chemistry pracs are doing my head in, great to have a challenge, from chemicals kids aren't to use and shouldn't be using, to mind reading some of it.

NOW asking for 5 x 10-4molL-1 iron (III) thiocyanate = 0.0005m is that right? hate looking like an idiot! Practical investigation of an equilibrium system

Did every ones students have success with Determination of Keq by colorimetry

only a little rant.

Just finished this prac for this year. I know the iron thiocyanate has to be made fresh, but can the 0.002M KSCN and the 0.002M Fe(NO3)3 be kept until next year? ie: what is the shelf life for these solutions?

Thanks
Kathryn

We just used the ones I mixed last year with great success

My chem teacher got me to keep the solution from last year which he was happy to use this year. As far as I know, it all worked fine.

Hi Kathryn,

Official shelf life doesn't always indicate loss of reactivity. I'm still using the same solutions three or four years later with good results.

Marama

Hi Marama,

I prepared these solutions just yesterday just wondering did your chem teacher use a spectrometer to get the absorbance of the solutions and if yes,what type of results did you get?I think our Keq is a little out

Thanks Happy labby

Hi Happy Labby,

No, sorry, I can't help you with that. We didn't use a spectrometer.

Marama

Hi Everyone,
Did anyone use a spectrometer to get the absorbance of the solutions? and if yes could they share the results with me

Many thanks
Happy Labby

can anyone tell me how to make this
iron (iii) thiocyanate ion solution

thank you in advance

I have merged them for you Kimmy

Hi All
Need help PLEASE
making iron (lll) thiocyanate
I have no idea
THANK YOU
Judy

Hi Judy.
Search iron thiocyanate in the search box above and you'll see previous discussions on this.
J

Hope this helps Judy2018