Halogen ion lab
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Transcript of Halogen ion lab
8 drops
NaF NaCl NaBr NaI
Now add calcium nitrate to each tube
Added calcium nitrate to each tube.
NaF NaCl NaBr NaI
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!
NaI NaBr NaClNaF
Now add silver nitrate to each tube
Added silver nitrate to each tube
NaI NaBr NaCl NaF
What could be causing the precipitate in the tubes?
NaClNaBrNaI
Added silver nitrate
NaCl + silver nitrate = precipitateNaBr + silver nitrate = precipitateNaI + silver nitrate = precipitate
NaCl + silver nitrate = sodium nitrate + silver chlorideWhich one is the precipitate?
Look at your solubility chart>
Group I has weak attractionto every – ion; Nitrate has weakattraction to every + ion
Silver has strong attraction toiodine, bromine and chlorine ions.
1st add ammonium hydroxide to each of the tubes containing precipitates, then later add sodium thiosulfate to each one
1. Now add ammonium hydroxide to each tube.
1.
2. Now add sodium thiosulfate to each tube.
2.
I Br Cl F Dissolved
Dissolved
I Br Cl F
I Br Cl F
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.