week 10 Sapling Q7

[Tiao Tan 3C]

I am stuck with this problem. Could someone tell me what I did wrong?
The feedback says I have not identified all the basic salts.
Much appreciated

[claire ikemiya_2I]

k2s03 is actually basic too. since the anion is derived from a weak acid, it will pull an H+

[Anna_Mohling_1D]

It also really helps me to separate the given salt/ion before I even consider ranking them! I do this because then it's easier to identify which may come from strong bases or acids!

[MCalcagnie_ 1D]

I actually noticed separating them helped me too! It got to confusing trying to figure out which is what, so separating the cation and anion and then comparing made a huge difference.

[Alexa Pham 1D]

Yeah, I also separate the cation and anion of the salt and see how each one would react with water -- whether it will produce H3O+ or OH-. The conjugate bases of strong acids won't react with water though so keep that in mind. Same thing goes for conjugate acids of strong bases. So K₂SO₃ would be a basic salt because if we separate the cation and anion, there would be two K+ and an SO₃^-2. K+ is the conjugate acid of a strong base so that will not react with water. SO₃^-2 however, will react with water. It will accept an H+ from H₂O and so the products of that reaction will be HSO₃^- and OH-. Since OH- was produced, we know that the pH will be greater than 7 -- in other words, the solution will be basic.

[Savannah Torella 1L]

I also struggled with this problem. K2SO3 would be basic since SO3^2- could accept a H+ from water, producing HSO3^- and OH-. Since OH- was produced, this whole compound is basic.