Test for halides

Introductory chemistry demonstrations in the laboratory | Test for chloride, bromide and iodide using silver nitrate | www.learnscience.co.za

[@anbudamodaran4162]

Am I the only person who barely sees a difference in the precipitate colors? I know that its supposed to be white, cream, and yellow, but I thought the difference in colour would be way more distinct

[@LearnScienceCoZa]

True - the difference is rather slight. Add nitric acid to each of the precipitates to make the difference clearer. This turns the cream bromide precipitate orange and the yellow iodide precipitate black. Pity I didn't include that in the movie...

[@jamesmccabe3470]

It can be difficult to see the difference so a further step is to add dilute ammonia. When you do that you find that the silver chloride will dissolve but the silver bromide and silver iodide will not. Then you can add concentrated ammonia to the silver bromide and silver iodide and you will see that the silver bromide will dissolve. The only one that doesn't dissolve in either is the silver iodide.

[@AbdullahShahid-ir6gj]

i have a test on this tomorrow and i cant see the difference, WHAT AM I GOING TO DO!!?!?!?!

[@Eeveeingslikethis]

Really good video, definitely helped for my exam today XD

[@hashiramauchiha2877]

@@ramnivaskumar8354 thank you 😊

[@hashiramauchiha2877]

@@ramnivaskumar8354 but I said to you

[@yousufkhn14]

u fail i pass

[@blazeranger7431]

This test is carried out in a fume cubboard right??

[@louistournas120]

Add Cu(2+). It would react with the I- forming CuI (solid) and I2. Adding Cu(2+) to Br- and Cl- does not form a solid and does not oxidize Cl- and Br-.

[@cyberconsumer5144]

Thank you.

[@hazza6603]

Please reply ASAP someone. Why did you not add Nitric acid? In some resources, nitric acid and silver nitrate were added to the solutions...

[@studilicious8844]

we add nitric acid incase we have any carbonates in the halide solution to prevent the formation of SilverCarbonate that will mask ur halide observations, im guessing she didnt add nitric acid here cuz she already knows theres no carbonates and only potassium

[@hazza6603]

grungekitty ok thank you so much. Couldn't find the answer anywhere.

[@mariokart6118]

It's good practice to add nitric acid

[@ankursardar4707]

@@studilicious8844 you need to add HNO3 to use the common ion effect and by this combination of HNO3 and silver nitrate then only free silver ions will react with free halide ions please dont put some random theory and we get white for chloride, pale yellow for bromide and yellow for iodide