An acid is a substance which dissolves in water to form hydrogen ion as the only positive ion OR an acid is a proton donor.

Eg:      HCL(aq)→H(aq)++Cl(aq)-

Acids can be classified into two main groups namely:

• Organic acids
• Mineral acids

Organic acids originate from substances such as plants and animals. Eg: Ethanoic acid, Tartaric acid, Citric acid.

Mineral acids originate from rocks. Eg: Hydrochloric acid (HCL), Sulphuric acid (H₂SO₄), Nitric acid (HNO₃).

STRONG AND WEAK ACIDS

• Strong Acids: They are acids which ionize completely in solution or water. Eg: HCL, H₂SO₄, HNO₃.

    HCL(aq)→H(aq)++Cl(aq)-

H2SO4→2H(aq)++SO4 (aq)2-

• Weak Acids: They will ionize partially in solution. Eg: Ethanoic acid, tartaric acid, carbonic acid.

CH3COOHaq↔CH3COO(aq)-+H(aq)+

BASICITY OF AN ACID

The Basicity of an acid is the number of hydrogen ions that one molecule of the acid will ionize to produce.

1. Mono Basic Acid

It is an acid that one molecule of it will ionize to produce only one hydrogen ion. Eg: Hydrochloric acid, Ethanoic acid.

    HCL(aq)→H(aq)++Cl(aq)-

CH3COOHaq↔CH3COO(aq)-+H(aq)+

2. Di basic Acid

This is an acid that one molecule of it will ionize to produce two hydrogen ions.

H2SO4→2H(aq)++SO4 (aq)2-

H2CO3→2H(aq)++CO3 (aq)2-

3. Tri basic Acid

It is an acid that one molecule of it will ionize to produce three hydrogen ions. Eg: Phosphoric acid, phosphorus acid.

H3PO4 (aq)→3H(aq)++PO4 (aq)3-

Physical Properties of Acids

• Acids turn moist litmus paper red.
• Acids are corrosive.
• Acids have a sour taste.
• Acids are soluble in water.
• Acids act as electrolytes
• Acids have a PH value less than 7

Preparation of Acids

1. SO2+H2O→H2SO3
2. CO2+H2O→H2CO3
3. P4O10+6H2O→4H3PO4
4. By direct combination

 H2 (g)+Cl2 (g)→2HCL(g) 

Chemical Properties of Acids

• Acids react with fairly reactive metals to produce H₂ gas.

Zn(s)+H2SO4(aq)→ZnCl2 (aq)+H2 (g)

• Acids react with metal oxides to produce salt and water

CuO(s)+H2SO4 (aq)→CuSO4 (aq)+H2O(l)

• Acids react with metal carbonates to produce salt, water and carbon dioxide.

CaCO3 (s)+2HCL(aq)→CaCl2 (aq)+H2O(l)+CO2 (g)

• Acids react with alkali to form salt and water

HC��(aq)+NaOH(aq)→NaCl(aq)+H2O

Uses of Acids

• In car batteries
• In producing fertilizers
• In the manufacture of soap
• In the manufacture of explosives. Eg: TNT.

  An acid is a substance which dissolves in water to form hydrogen ion as the only positive ion OR an acid is a proton donor.

  Eg:      HCL(aq)→H(aq)++Cl(aq)-

  Acids can be classified into two main groups namely:

• Organic acids
• Mineral acids

• Organic acids originate from substances such as plants and animals. Eg: Ethanoic acid, Tartaric acid, Citric acid.

  Mineral acids originate from rocks. Eg: Hydrochloric acid (HCL), Sulphuric acid (H₂SO₄), Nitric acid (HNO₃).

  STRONG AND WEAK ACIDS

• Strong Acids: They are acids which ionize completely in solution or water. Eg: HCL, H₂SO₄, HNO₃.

•     HCL(aq)→H(aq)++Cl(aq)-

  H2SO4→2H(aq)++SO4 (aq)2-

• Weak Acids: They will ionize partially in solution. Eg: Ethanoic acid, tartaric acid, carbonic acid.

• CH3COOHaq↔CH3COO(aq)-+H(aq)+

  BASICITY OF AN ACID

  The Basicity of an acid is the number of hydrogen ions that one molecule of the acid will ionize to produce.

• Mono Basic Acid

• It is an acid that one molecule of it will ionize to produce only one hydrogen ion. Eg: Hydrochloric acid, Ethanoic acid.

      HCL(aq)→H(aq)++Cl(aq)-

  CH3COOHaq↔CH3COO(aq)-+H(aq)+

   

   

• Di basic Acid

• This is an acid that one molecule of it will ionize to produce two hydrogen ions.

  H2SO4→2H(aq)++SO4 (aq)2-

  H2CO3→2H(aq)++CO3 (aq)2-

• Tri basic Acid

• It is an acid that one molecule of it will ionize to produce three hydrogen ions. Eg: Phosphoric acid, phosphorus acid.

  H3PO4 (aq)→3H(aq)++PO4 (aq)3-

  Physical Properties of Acids

• Acids turn moist litmus paper red.
• Acids are corrosive.
• Acids have a sour taste.
• Acids are soluble in water.
• Acids act as electrolytes
• Acids have a PH value less than 7

• Preparation of Acids

• SO2+H2O→H2SO3
• CO2+H2O→H2CO3
• P4O10+ par Claude Foumtum