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EfficientEagle2708

Hello I have a chemistry question. In class we learnt the concept that not all salt are neutral, if the composing ions of the salts come from a weak acid or a weak base then they will either be a basic salt or an acidic salt. Now here comes my issue, on my tests and exams they have been giving me salts and asking me if increasing/decreasing the pH of the solution will increase the salts solubility or decrease it.

Here is the logic I was taught via youtube, if you find urself with an ACIDIC salt and you increase pH (more BASIC conditions) then solubility will INCREASE, same thing is for the opposite, if you find urself with a basic salt and you decrease the ph (more acidic conditions) then solubility will increase. This has worked for me most of the time except for this question.

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NH4Br -> NH4^+ +Br^-

NH4^+ comes from a weak base therefore will make the salt ACIDIC

Br^- comes from a strong acid therefore will not effect

so at this point i'm under the impression that we are woking with an acidic salt, so if we increase the pH of the solution (more basic condition) then i would think the solubility increases.

i even watched multiple videos saying how it worked:

NH4^+ + H20 -> NH3 + H+

more basic conditions mean less H+ ions will form because they will be neutralized, so for equilibrium you need to use up more NH4^+ , now if you use up more NH4^+ then:

NH4Br -> NH4^+ +Br^-

there will be less NH4^+ so reaction shifts to right to produce more, therefore increasing the solubility. I AM SO CONFUSED BECAUSE THE ANSWER SAYS DECREASES SOLUBILITY! Someone please help with my logic of this question its supposed to be really important for my exam and i'm very worried now that apparently my logic of the question is wrong.

CitrineCandide143

Hi EfficientEagle2708,

Thanks for using our service.

Unfortunately, our service stop in secondary 5. You are in higher education, I advice you to go get help by your teacher. He will be better to help you.

Have a great day!

Lea-Kim