Acids and Bases

Acids

• Definition: A substance that donates a proton (H+ ion) in a solution
• Characteristics:
  • Sour taste
  • Conduct electricity
  • Turn blue litmus paper red
  • React with metals to produce hydrogen gas
• Examples:
  • Hydrochloric acid (HCl)
  • Sulfuric acid (H2SO4)
  • Nitric acid (HNO3)

Bases

• Definition: A substance that accepts a proton (H+ ion) in a solution
• Characteristics:
  • Bitter taste
  • Feel slippery to the touch
  • Conduct electricity
  • Turn red litmus paper blue
  • React with oils to produce soap
• Examples:
  • Sodium hydroxide (NaOH)
  • Calcium hydroxide (Ca(OH)2)
  • Ammonia (NH3)

pH Scale

• A scale used to measure the acidity or basicity of a solution
• Range: 0-14
• pH 7: Neutral (neither acidic nor basic)
• pH < 7: Acidic
• pH > 7: Basic

Salt

• Definition: A substance formed by the reaction between an acid and a base
• Characteristics:
  • Typically neutral in nature
  • Can be acidic or basic depending on the acid and base used
  • Often crystalline in nature
• Examples:
  • Sodium chloride (NaCl) - formed from HCl and NaOH
  • Calcium carbonate (CaCO3) - formed from H2CO3 and Ca(OH)2
  • Ammonium nitrate (NH4NO3) - formed from HNO3 and NH3

Strong and Weak Acids/Bases

• Strong acids:
  • Completely dissociate in water
  • Examples: HCl, H2SO4, HNO3
• Weak acids:
  • Partially dissociate in water
  • Examples: CH3COOH, HCN
• Strong bases:
  • Completely dissociate in water
  • Examples: NaOH, Ca(OH)2
• Weak bases:
  • Partially dissociate in water
  • Examples: NH3, CH3NH2

Acids

• Donate a proton (H+ ion) in a solution
• Characterized by sour taste, ability to conduct electricity, and turning blue litmus paper red
• React with metals to produce hydrogen gas
• Examples include hydrochloric acid (HCl), sulfuric acid (H2SO4), and nitric acid (HNO3)

Bases

• Accept a proton (H+ ion) in a solution
• Characterized by bitter taste, slippery texture, and ability to conduct electricity
• Turn red litmus paper blue and react with oils to produce soap
• Examples include sodium hydroxide (NaOH), calcium hydroxide (Ca(OH)2), and ammonia (NH3)

pH Scale

• Measures acidity or basicity of a solution
• Ranges from 0 to 14, with 7 being neutral
• pH values below 7 indicate acidity, while values above 7 indicate basicity

Salts

• Formed by the reaction between an acid and a base
• Typically neutral, but can be acidic or basic depending on the reactants
• Often crystalline in nature
• Examples include sodium chloride (NaCl), calcium carbonate (CaCO3), and ammonium nitrate (NH4NO3)

Acid and Base Strength

• Strong acids completely dissociate in water, examples include HCl, H2SO4, and HNO3
• Weak acids partially dissociate in water, examples include CH3COOH and HCN
• Strong bases completely dissociate in water, examples include NaOH and Ca(OH)2
• Weak bases partially dissociate in water, examples include NH3 and CH3NH2