Question

Determine whether each of the following will form a solution that is acidic, basic, or pH-neutral.

1) Fe(NO₃)₃

2) KCl

3) K₂CO₃

4)CH₃NH₃Cl

5) C₂H₅NH₃CN

Answer 1

1) Fe(NO3)3 --> Fe+3 ions in solution, they will react with water

Fe+3 + H2O <--> Fe(OH)3 + H+; slighlty ACIDIC

2) KCl

strong acid/base salt, expect this to be neutral

3) K2CO3

CO3-2 in solution... react with water to form

CO3-2 + H2O <--> H2CO3 + OH-; slightly BASIC

4)CH3NH3Cl

CH3NH3+ in solutoin, they react to form

CH3NH3+ + H2O <--> CH3NH2 + H3O+; slightly ACIDIC

5) C2H5NH3CN

C2H5NH3+ and CN-

C2H5NH3+ --> Kb = 10^-4

CN- --> Ka = 10^-9

then, this will be slighlty ACIDIC