Question

1- Write the equations for the reaction of the following Bronsted acids with water:

(a)H2O . (b)H2AsO4- (c) H2AsO4

2-Write the equations for the reaction of the following Bronsted acids with water:

(a)CH3CO2- (b) HAsO4 2- (c) (CH3)3N

3- Give the letters of the solutions below that represent buffers:

a- a solution of sodium hydrogen carbonate and sodium carbonate

b- a solution of sodium dihydrogen phosphate in water

c- a solution of ammonia and ammonium chloride

d- a solution of acetic acid and sodium acetate

Answer 1

Q1. (a) H₂O + H₂O H₃O⁺ + OH^-

(b) H₂AsO₄^- + H₂O HAsO₄^2- + H₃O⁺

(c) H₂AsO₄ + H₂O HAsO₄^- + H₃O⁺

Q2. (a) CH₃CO₂^- + H₂O CH₃CO₂H + OH^-

(b) HAsO₄^2- + H₂O H₂AsO₄^- + OH^-

(c) (CH₃)₃N + H₂O (CH₃)₃NH⁺ + OH^-

Q3. The solutions that represent buffers are :

• a- a solution of sodium hydrogen carbonate and sodium carbonate

• c- a solution of ammonia and ammonium chloride

• d- a solution of acetic acid and sodium acetate