![PROPERTIES OF ACIDS
- Produce hydrogen ions [H+] in H2O.
– Sour taste.
– Turn blue litmus red.
– Act as electrolytes in Solution.
– Neutralize solutions carrying hydroxide ions.
– React with several metals releasing Hydrogen gas.
– React with carbonates releasing CO2 (g)
– Destroy body tissues.
– corrode metal surface quickly.](https://image.slidesharecdn.com/classificationofacidsbases-200501184133/85/Classification-of-acids-bases-8-320.jpg)
![PROPERTIES OF BASES
- Produce hydroxide ions [OH –] in H2O.
– Water soluble bases are called alkalies.
– Bitter Taste
– Turn Red Litmus blue.
– Act as electrolytes in Solution.
– Neutralize solutions containing H+ ions.
– Have a slippery, ‘soapy’ feel.
– Dissolve fatty material.](https://image.slidesharecdn.com/classificationofacidsbases-200501184133/85/Classification-of-acids-bases-18-320.jpg)
Classification of acids & bases
- 1. BY: MS VEENU GUPTA (PGT CHEMISTRY) APS RAKHMUTHI
- 2. ACIDS Acid is a compound which yields hydrogen ion (H+), when dissolved in water.
- 3. Examples of commonly used acids Hydrochloric acid (HCl) Nitric acid (HNO3) Sulphuric acid (H2SO4) Carbonic acid (H2CO3) Phosphoric acid (H3PO4) Acetic acid (CH3COOH)
- 4. ACTION OF ACIDS IN WATER Hydrochloric acid (HCl) gives hydrogen ion (H+) and chloride ion (Cl–) when it is dissolved in water. HCl + H2O → H3O+ + Cl- Nitric acid (HNO3) gives hydrogen ion (H+) and nitrate ion (NO3 -) when it is dissolved in water. HNO3 + H2O → H3O+ + NO3 - Sulphuric acid (H2SO4) gives hydrogen ion (H+) and sulphate ion (SO4 2-) when it is dissolved in water. H2SO4 + H2O → H3O+ + SO4 2-
- 5. Carbonic acid (H2CO3) gives hydrogen ion (H+) and carbonate ion (CO3 2-) when it is dissolved in water. H2CO3 + H2O → H3O+ + CO3 2- Acetic acid (CH3COOH) gives acetate ion (CH3COO–) and hydrogen ion (H+). CH3COOH + H2O → CH3COO– + H3O+ Phosphoric acid (H3PO4) gives hydrogen ion (H+) and phosphate ion (PO4 3-) when it is dissolved in water. H3PO4 + H2O → H3O+ + PO4 3- Thus, those compound which yields hydrogen ion (H+), when dissolved in water are called acids.
- 6. CHEMISTRY OF ACIDS IN WATER: When an acid is dissolved in water, it dissociates hydrogen. The dissociation of hydrogen ion in aqueous solution is the common property in all acids. Because of the dissociation of hydrogen ion in aqueous solution, an acid shows acidic behaviour. Examples: Hydrochloric acid (HCl) gives hydrogen ion (H+) and chloride ion (Cl–) when it is dissolved in water. Acetic acid (CH3COOH) gives acetate ion (CH3COO–) and hydrogen ion (H+). It conducts electricity. Decrease in H30+ ions concentration per unit volume results in formation of dilute acids.
- 7. NATURE OF RXN OF ACIDS IN WATER Acids when dissolved in water,they release a large amount of heat as it is a highly exothermic reaction. So to make acidic solution, acids must be added drop wise into water with constant stirring, so that the heat generated spreads over in water. Acids produce H+ ions when dissolved in water. H+ ions cannot exist alone. They combine with water molecule (H2O) to form H3O+ (hydronium ions). HCl + H2O → H3O+ + Cl–
- 8. PROPERTIES OF ACIDS - Produce hydrogen ions [H+] in H2O. – Sour taste. – Turn blue litmus red. – Act as electrolytes in Solution. – Neutralize solutions carrying hydroxide ions. – React with several metals releasing Hydrogen gas. – React with carbonates releasing CO2 (g) – Destroy body tissues. – corrode metal surface quickly.
- 9. CLASSIFICATION OF ACIDS ON THE BASIS OF ORIGIN ON THE BASIS OF STRENGTH ON THE BASIS OF CONCENTRATION ON THE BASIS OF HYDROGEN ION
- 10. ON THE BASIS OF ORIGIN Organic acids: Acids derived from living organisms like plants and animals . For example: citric acid is present in fruits, acetic acid present in vinegar, oxalic acid present in tomato, tartaric acid present in tamarind, lactic acid present in sour milk and curd. Mineral acids: They are also called inorganic acids. They are dangerous Example sulphuric acid (H2SO4), hydrochloric acid (HCl) etc.
- 11. SOURCES OF ORGANIC ACIDS Organic Acids Sources Acetic acid Vinegar Ascorbic acid Guava, amla Citric acid Lemon, orange and other citrus fruits Lactic acid Sour milk, curd Methanoic acid Ant sting, nettle sting Oxalic acid Tomato Tartaric acid Tamarind
- 12. ON THE BASIS OF STRENGTH Strong acids: Completely dissociate into its ions in aqueous solutions. Example: Nitric acid (HNO3), sulphuric acid (H2SO4), hydrochloric acid (HCl). Weak acids: Weak acids are those acids which do not completely dissociate into its ions in aqueous solutions. For example: carbonic acid (H2CO3), acetic acid (CH3COOH)
- 13. ON THE BASIS OF CONCENTRATION Dilute acids: Have a low concentration of acids in aqueous solutions. Decrease in H+ ions single concentration per unit volume results in formation of dilute acids. Concentrated acids: Have a high concentration of acids in aqueous solutions. Increase in H+ ions single concentration per unit volume results in formation of conc. acids.
- 14. ON THE BASIS OF HYDROGEN ION Monoprotic acid – Such type of acid produces one mole of H+ ions per mole of acid. e.g., HCl , HNO3 Diprotic acid – They can produce two moles of H+ ions per mole of acid, e.g., H2SO4. Triprotic acid – They produce three moles of H+ ions per mole of acid, e.g., H3PO4. Polyprotic – They can produce more than three H+ ions per mole of acid.
- 15. BASES Bases are bitter in taste, have soapy touch, turn red litmus blue and give hydroxide ions (OH–) in aqueous solution. Examples: Sodium hydroxide (caustic soda) – NaOH Calcium hydroxide – Ca(OH)2 Potassium hydroxide (caustic potash) – (KOH)
- 16. ACTION OF BASES ON WATER Bases generate OH- ions in water 1. NaOH (aq) + H2O → Na+ (aq) + OH– (aq) 2. KOH (aq) + H2O → K+ (aq) + OH– (aq) 3. Ca(OH)2 (aq) + H2O → Ca2+ (aq) + OH– (aq) 4. NH3 (g) + H2O (l) →NH4OH (aq) NH4OH (aq) → NH4 + (aq) + OH- (aq)
- 17. ALKALI VS BASES All bases do not dissolve in water. An alkali is a base that dissolves in water. Common alkalis are: NaOH -Sodium hydroxide KOH - Potassium hydroxide Ca(OH)2 -Calcium hydroxide NH4OH -Ammonium hydroxide Note : All alkalis are bases but all bases are not alkalis.
- 18. PROPERTIES OF BASES - Produce hydroxide ions [OH –] in H2O. – Water soluble bases are called alkalies. – Bitter Taste – Turn Red Litmus blue. – Act as electrolytes in Solution. – Neutralize solutions containing H+ ions. – Have a slippery, ‘soapy’ feel. – Dissolve fatty material.
- 20. ON THE BASIS OF STRENGTH Strong bases: Strong bases are those bases which completely dissociate into its ions in aqueous solutions. Example: sodium hydroxide (NaOH), potassium hydroxide (KOH). Weak bases: Weak bases are those bases which do not completely dissociate into its ions in aqueous solutions. For example: ammonium hydroxide (NH4OH).
- 21. ON THE BASIS OF CONCENTRATION Dilute bases: Have a low concentration of alkali in aqueous solutions. Decrease in OH– ions single concentration per unit volume results in formation of dilute bases. Concentrated bases: Have a high concentration of alkali in aqueous solutions. Increase in OH– ions single concentration per unit volume results in formation of conc. bases.
- 22. CHEMISTRY OF BASES IN WATER: Bases produce OH– ions when dissolved in water. Bases which are soluble in water are called alkalis. It conducts electricity. Decrease in OH– ions single concentration per unit volume results in formation of dilute bases. Bases when dissolved in water release large amount of heat as it is a exothermic reaction. So to make basic solution, base must be added drop wise into water with constant stirring, so that the heat generated spreads over in water.