Inorganic chemistry Assistance Lecturer Amjad Ahmed Jumaa  Strong and Weak acids.  Strong and Weak bases.  Reaction of Acids 1

 Many foods are acidic, cider vinegar contains acetic acid, lemons and other citrus fruits as well as many fruit- flavored drinks contain citric acid.  Strong and Weak acids: In Arrhenius theory:  A strong acid: Is a substance that completely ionize in aqueous solution to give H 3 O + (aq) and an anion. An example is perchloric acid HClO 4.

HClO 4 (aq) + H 2 O ( l ) → H 3 O + (aq) + ClO 4 - (aq). Other examples of strong acid are HCl, HI, HBr, HCl, and HNO 3. HClO 4 (aq) + H 2 O ( l ) → H 3 O + (aq) + ClO 4 - (aq). Other examples of strong acid are HCl, HI, HBr, HCl, and HNO 3.  A Weak acids: They are not completely ionized in solution and exist in reversible reaction with the corresponding ions. Consider acetic acid, CH 3 CO 2 H, the reaction is: CH 3 CO 2 (aq) + H 2 O ↔ H 3 O + (aq) + CH 3 CO 2 - (aq).

4  Strong and Weak bases: A strong base : Completely ionizes in aqueous solution to give a hydroxide ion, OH - and a cation. Sodium hydroxide is an example of a strong base:  Strong and Weak bases: A strong base : Completely ionizes in aqueous solution to give a hydroxide ion, OH - and a cation. Sodium hydroxide is an example of a strong base: NaOH(s) Na + (aq) + OH - (aq

 A Weak bases: They are not completely ionized in solution and exist in reversible reaction with corresponding ions. Consider the aniline C 6 H 5 NH 2 : C 6 H 5 NH 2 (aq) + H 2 O( l ) ↔ C 6 H 5 NH OH - (aq).  A Weak bases: They are not completely ionized in solution and exist in reversible reaction with corresponding ions. Consider the aniline C 6 H 5 NH 2 : C 6 H 5 NH 2 (aq) + H 2 O( l ) ↔ C 6 H 5 NH OH - (aq).

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 Reaction of Acids: 1- Neutralization: a double-replacement: Acid+ base → water + salt Example: HCl(aq) + NaOH(aq) → H 2 O( l ) + NaCl(aq).  Reaction of Acids: 1- Neutralization: a double-replacement: Acid+ base → water + salt Example: HCl(aq) + NaOH(aq) → H 2 O( l ) + NaCl(aq). 2-Reaction of acid with active metals, single replacement. Acid + active metal → hydrogen gas + salt. H 2 SO 4 (aq) + Zn(s) → H 2 (g) +ZnSO 4 (aq). 2-Reaction of acid with active metals, single replacement. Acid + active metal → hydrogen gas + salt. H 2 SO 4 (aq) + Zn(s) → H 2 (g) +ZnSO 4 (aq). 3- Reaction of acids with metal oxides: Acid + metal oxide → water + salt 2HCl(aq) + CaO(s) → H 2 O( l ) + CaCl 2 (aq). 3- Reaction of acids with metal oxides: Acid + metal oxide → water + salt 2HCl(aq) + CaO(s) → H 2 O( l ) + CaCl 2 (aq).

4- Reaction of acids with carbonates: Acid + carbonate → salt + carbon dioxide + water. 2HCl(aq) + CaCO 3 (s) → CaCl 2 (aq) + CO 2 (g) + H 2 O( l ). 5- Reaction of acid with metal sulfides: Acid + metal sulfide → salt + hydrogen sulfide gas. H 2 SO 4 (aq) + FeS(s) → FeSO 4 (aq) + H 2 S(g). 4- Reaction of acids with carbonates: Acid + carbonate → salt + carbon dioxide + water. 2HCl(aq) + CaCO 3 (s) → CaCl 2 (aq) + CO 2 (g) + H 2 O( l ). 5- Reaction of acid with metal sulfides: Acid + metal sulfide → salt + hydrogen sulfide gas. H 2 SO 4 (aq) + FeS(s) → FeSO 4 (aq) + H 2 S(g). Q) Write a balanced chemical equation for the reaction of sodium hydrogen carbonate with acetic acid? Answer: NaHCO 3 (s) + CH 3 CO 2 H → NaCH 3 COO(aq) +H 2 O + CO 2 (g). Q) Write a balanced chemical equation for the reaction of sodium hydrogen carbonate with acetic acid? Answer: NaHCO 3 (s) + CH 3 CO 2 H → NaCH 3 COO(aq) +H 2 O + CO 2 (g).