[akaEMILY]

So I've been given a bunch of salts and I'm trying to categorize them.. I some how got them wrong. Could you catch my error?


Na(HOOCCOO): I assumed this is acidic because the Na is a spectator ion and then it would be HOOCCOO- which is acidic.
NaHSO3: Na is a spectator ion and HSO3- is basic.
RbCl: Rb doesn't react in water so I thought it would be neutral for Cl.
NaHCOO: Na is a spectator and HCOO is basic.
SrI2: Sr doesn't react in water so I assumed it would be neutral.

[Borek]

Looks OK to me.

[AWK]

NaHSO₃ - pH ~4.5

[Borek]

Yep, sorry.

[akaEMILY]

Thanks so much.. wow that was a little stressful!

[XGen]

I had looked at these and thought that these were ones you got wrong so I was doubting my own ability to judge salts

[Wastrel]

Na⁺ is not a spectator.  Take NaHCOO.  The remaining hydrogen is connected to the carbon so it can be ignored and this is a salt (as opposed to an acid salt).  Sodium formate is a salt of a strong base (NaOH) and a weak acid (HCOOH, organic and therefore weak) and is overall slightly basic.  The salt of a strong acid and a weak base, for example NH₄Cl is the salt of NH₄OH and HCl, would be slightly acid.  When they are both strong or both weak they cancel out and become neutral.

[Borek]

In the case of sodium formate I see nothing wrong with calling Na⁺ a spectator. It doesn't change during the formate hydrolysis.

When they are both strong or both weak they cancel out and become neutral.

Not necessarily. Ammonium acetate solution is always neutral, aniline formate solution is always acidic, methylamine cyanate solution is always basic.

[Wastrel]

I agree with both points, you can say the reason Na⁺ is mostly a spectator is because NaOH is such a strong base but for me this is a property of NaOH.  Maybe this is an artifact of different ways of teaching, here this is A level and things were taught to me from the easier point of view of the acid and base forming the salt, not the conjugates.