Question

Determine if the following is acidic, basic or neutral Ba(I)2 NH4NO3 Li2S (is there some kind of trick to do this )

For the following reaction, predict whether the equilibrium lies predominantly to the left or to the right. (how do I figure it out by looking at the equation)

HPO42-(aq) + CH3CO2-(aq) (arrow going both ways) PO43- + CH3CO2H

Answer 1

There is no "trick" you just need to know if they will form acids/bases or even OH- or H+ in solution so:

Ba(I)2 --> Ba+2 and 2I-

Ba+2 reacts with water to form Ba(OH)2 + 2H+ ... that is ACIDIC

NH4NO3 --> NH4+ + NO3-

NH4+ + H2O <-> NH3 + H3O+; which is acidic

Li2S --> 2Li+ + S-2

S-2 + H2O <--> HS + OH- ---> basic

2)

HPO42-(aq) + CH3CO2-(aq) (arrow going both ways) PO43- + CH3CO2H

actually, you need to know that:

HPO4-2 may be an acid/base

CH3CO2 can only be an acid

the "strongest" acid will give off th eH+, the weakest acid the H+

HPO4-2 and H2PO4- have pKa about 7

CH3CO2H has a pKa about 4.7

therefore, the acetic acid is stronger, meaning it will give off its H+

the left side is expected to be high in concnetrations