Question

State whether each of the following aqueous solutions would be acidic, basic, or neutral and explain your answer.

Include the appropriate net-ionic equations to show why a given solution is acidic or basic. Use Ka or Kb values if needed.

a. HCO₂H

b. 50:50 mixture of HCO₂H + NaHCO₂

c. ((CH₃)₂NH₂)Cl

d. 50:50 mixture of (CH₃)₂)NH + ((CH₃)₂NH₂)Cl

Answer 1

a) HCO2H

The solution of formic acid is acidic as in aqueous solution it give H+ ions.

HCO2H + H2O <------------> HCO2- + H3O+

b) acidic solution of a bufffer

HCO2H + H2O <------------> HCO2- + H3O+

HCO2- + H2O <------------> HCO2H + OH-

c) [(CH3)2NH2]Cl

The aqueous solution of thisis acidic in nature as it is a salt of weak base(CH3)2NH and strong acid HCl.

the ionic equation is

[(CH3)2NH2]⁺ + Cl^- + H2O <--------------> (CH3)2NH + H3O+ + Cl-

and the net ionic equation i

[(CH3)2NH2]⁺ + H2O <--------------> (CH3)2NH + H3O⁺

d)

A 50: 50 mixtrue of weak base (CH#)2NH and its salt [(CH3)2NH2]Cl behaves as a buffer is a basic bufer .

Thus the solution is basic in nature.

The net ionic equations in water is

[(CH3)2NH2]⁺ + H2O <--------------> (CH3)2NH + H3O⁺

(CH3)2NH2 + H2O <--------------> [(CH3)2NH2]⁺ + OH-