Project:Deactivating a ferric chloride solution: Difference between revisions

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=== In Theory ===
=== In Theory ===


Chemically the reaction is Ferric Chloride reacting to Sodium Hydroxide turning into Ferric Hydroxide and Sodium Chloride.
Ferric chloride reacts with sodium hydroxide turning into ferric hydroxide and sodium chloride.


FeCl<sub>3</sub> + 3 NaOH → Fe(OH)<sub>3</sub> + 3 NaCl
FeCl<sub>3</sub> + 3 NaOH → Fe(OH)<sub>3</sub> + 3 NaCl
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The proportions are:
The proportions are:


1 mole of FeCl<sub>3</sub> which is 91,3g reacting with 3 moles of Sodium Hydroxide 3 NaOH which is 120g.
1 mole of FeCl<sub>3</sub> which is 91,3g reacting with 3 moles of NaOH which is 120g.


The mass of 1 mole is obtained by adding together the atomic masses obtained from the periodic table of elements:
The mass of 1 mole is obtained by adding together the atomic masses obtained from the periodic table of elements:
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Chlorine (Cl) has the atomic mass of 35,5 (grams/mole) and Iron (Fe) has the atomic mass of 55.8 (grams/mole).
Chlorine (Cl) has the atomic mass of 35,5 (grams/mole) and Iron (Fe) has the atomic mass of 55.8 (grams/mole).


Ferric Chloride (FeCl<sub>3</sub>) will then have the molecular mass of 55.8 * 1 + 35.5 * 3 = 162.3 g/mole.
Ferric chloride (FeCl<sub>3</sub>) will then have the molecular mass of 55.8 * 1 + 35.5 * 3 = 162.3 g/mole.


To find how many moles are contained in 300 grams of Ferric Chloride the calculation is 300/162.3 = 1.85 moles of Ferric Chloride.
To find how many moles are contained in 300 grams of ferric chloride the calculation is 300/162.3 = 1.85 moles of ferric chloride.


Each mole of FeCl<sub>3</sub> requires 3 moles of NaOH (Sodium Hydroxide) at 40 grams per mole.
Each mole of FeCl<sub>3</sub> requires 3 moles of NaOH (sodium hydroxide) at 40 grams per mole.


The weight of Na0H required to deactivate the spent FeCl<sub>3</sub> solution is obtained thus:
The weight of Na0H required to deactivate the spent FeCl<sub>3</sub> solution is obtained thus:


1.85 * 3 = 5.55 moles of NaOH, at 40 g/mole that will be 5.55 * 40 = 222 grams NaOH.
1.85 * 3 = 5.55 moles of NaOH, at 40 g/mole that will be 5.55 * 40 = 222 grams NaOH.
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