# Calculate the activity of the chloride ion in a solution

• Chemistry
• il postino

#### il postino

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!

What is the concentration of Cl-?

• il postino
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?

• il postino
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.

• il postino
And for a given I what is the activity coefficient for an ion with a single charge?

aCl−=mCl−∗γCl−
Plug and chug.

Muchas gracias Borek! (In Argentina jaja)
Thanks!