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Required Practical 4 - Alevel Chem

What kind of questions can/do they ask when you're actually doing the practical?
My practical is tomorrow and i feel like I'm not prepared
One question I've heard is why add in silver nitrate

Reply 1

BankaiGintoki

Original post by Jay.4

What kind of questions can/do they ask when you're actually doing the practical?
My practical is tomorrow and i feel like I'm not prepared
One question I've heard is why add in silver nitrate

You add AgNO3 because:
Ag+ + X- (halide ion, Cl-, Br-, I-) -> forms AgX (s) [white, cream, yellow]
Before halide test, you add excess nitric acid (to react with carbonate ions) that would form Ag2CO3.

You may be asked why you might be doing a particular test, or how the test works.