Chemistry Calculate the activity of the chloride ion in a solution

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To calculate the activity of the chloride ion (Cl-) in a mixed solution of Na2SO4, NaCl, and FeCl3, the total concentration of Cl- is determined to be 0.0026 m. The ionic strength (I) of the solution is calculated as 0.0134. The activity of Cl- can be found using the formula aCl- = mCl- * γCl-, where γCl- is the activity coefficient. The activity coefficient can be estimated using the equation log(γCl) = -A |Z| √I, where A is a constant and Z is the charge of the ion. Once γCl- is calculated, the activity can be determined easily.
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Homework Statement
Calculate the activity of the chloride ion in a solution
Relevant Equations
Ionic force
Hi everyone!
I have to calculate the activity of ##Cl^{-}##
I have a solution formed by ## Na_{2}SO_{4}## 0.0016 m + ##NaCl## 0.0014m + ##FeCl_{3}## 0.0012m

I calculated the ionic strength ##I##
##I=0.0134##

The activity of the chloride ion is ##a_{Cl^{-}}=m_{Cl}*\gamma _{Cl}##

But I don't understand how to continue when it is a mix.
Could you help me?
Thank you very much!
 
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What is the concentration of Cl-?
 
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Borek said:
What is the concentration of Cl-?

0.0014m + 0.0012m = 0,0026m

How do I continue?
Thanks Borek
 
And for a given I what is the activity coefficient for an ion with a single charge?
 
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Borek said:
And for a given I what is the activity coefficient for an ion with a single charge?

##m_{Cl}*\gamma _{Cl}##

##log(\gamma _{Cl})=-A.|Z|.\sqrt{I}##

If I calculate ##\gamma _{Cl}## can I calculate the activity without problems?
 
Plug and chug.
 
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Borek said:
And for a given I what is the activity coefficient for an ion with a single charge?

aCl−=mCl−∗γCl−
Borek said:
Plug and chug.

Muchas gracias Borek! (In Argentina jaja)
Thanks!
 
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