[Archdevil155]

Yea I met with my former Chem teacher that I mentioned before and he explained it quite well.. And now I get what you mean about NH₃, thanks for all the help man.. He said that the way it's said in the Lab guide book (some dense NH₃) it means that it doesn't react because it's too little compared to the CaCl₂ and it's just there to adjust the pH and neutralize HPO₄^2-, just as you said.. Thanks again and now I'm writing and completing the report

[Archdevil155]

Sorry to ask again on this topic, but can you type the dissociation equation of Na₂HPO₄ * 12H₂O in water please??

It's in solid state in the form of small crystals-powder, if that's any help..

[Arkcon]

Sorry to ask again on this topic, but can you type the dissociation equation of Na₂HPO₄ * 12H₂O in water please??

What ions do you expect to be able to get, given the formula?  Take a random stab, see what you get, we can help afterward.

It's in solid state in the form of small crystals-powder, if that's any help..

None of that has any bearing on this question.  I hope you can see that.  Note: the water of hydration likewise has no effect on this problem, I hope you can see that.

[Archdevil155]

Yea I thought so just making sure.. My problem wasn't about Na₂HPO₄ but the 12H₂O. Whether they do something or not.. I didn't really think so but I wanted to know for sure. Na₂HPO₄  2Na⁺ + HPO₄^2-. So since the 12H₂O don't participate in the chemical equation I'm covered..

[Arkcon]

So what would happen to 12 molecules of H₂O locked into the solid's crystal lattice when the solid dissolves in water?  Can you determine how many molecules of water there are in 1 ml?  That would help you understand.

[alejmam]

sorry to bother or spam the conversation but I'd like to ask you if you study in Patra because I'm in the exact place with this experiment as you are .