1. Halogen ion lab

2. 8 drops

3. First reaction

4. Now add calcium nitrate to each tube
NaF
NaCl
NaBr
NaI
Now add calcium nitrate to each tube

5. Added calcium nitrate to each tube.
NaF
NaCl
NaBr
NaI
Added calcium nitrate to each tube.

6. Calcium nitrate + sodium fluoride = a precipitate
What could it be?
Calcium nitrate + NaF === calcium fluoride + sodium nitrate
which is the precipitate???”
Now balance the equation!

7. Second Reaction

8. Now add silver nitrate to each tube
NaI
NaBr
NaCl
NaF
Now add silver nitrate to each tube

9. Added silver nitrate to each tube
NaCl
NaF
NaI
NaBr
Added silver nitrate to each tube

10. NaCl + silver nitrate = sodium nitrate + silver chloride
What could be causing the
precipitate in the tubes?
Added silver nitrate
Group I has weak attraction
to every – ion; Nitrate has weak
attraction to every + ion
Silver has strong attraction to
iodine, bromine and chlorine
ions.
NaI
NaBr
NaCl
NaCl + silver nitrate = precipitate
NaBr + silver nitrate = precipitate
NaI + silver nitrate = precipitate
NaCl + silver nitrate = sodium nitrate + silver chloride
Look at your solubility chart>
Which one is the precipitate?

11. Another reaction 1st add ammonium hydroxide to each of the
tubes containing precipitates, then later add
sodium thiosulfate to each one

12. 1. Now add ammonium hydroxide to each tube. 2. Now add sodium
I Br Cl F
Dissolved
I Br Cl F 1. 2.
1. Now add ammonium
hydroxide to each tube.
I Br Cl F
2. Now add sodium
thiosulfate
to each tube.
Dissolved

13. AgCl + ammonium hydroxide = precipitate dissolves….
AgBr + sodium thiosulfate = precipitate dissolves
AgI doesn’t dissolve with either solution.
You can try to predict what the balanced equations might be.
If you read the lab and look carefully you can write balanced
equation for the reaction where AgCl dissolves and AgBr dissolves.
However this is not absolutely required in the lab.