Acids and Bases Summary

Acids and Bases

• Fundamental chemical compounds essential for industrial processes and everyday products.

Arrhenius Definition of Acids and Bases

• Acids: Produce hydrogen ions (H+) in water.
  Example: $HCl \rightarrow H^+ + Cl^-$
• Bases: Produce hydroxide ions (OH-) in water.
  Example: $NaOH \rightarrow Na^+ + OH^-$
• Historical Impact: Proposed by Svante Arrhenius in 1884, revolutionizing chemical reaction understanding.

Nomenclature of Acids

• Binary Acids: Begin with "hydro-", end with "-ic acid"
  Example: $HCl = \text{hydrochloric acid}$
• Oxoacids:
  • Higher Oxygen: Element root + "-ic acid"
    Example: $H<em>2SO</em>4 = \text{sulfuric acid}$
  • Lower Oxygen: Element root + "-ous acid"
    Example: $H<em>2SO</em>3 = \text{sulfurous acid}$

Nomenclature of Bases

• Base Naming Convention: Metal name + hydroxide Examples:
  • $NaOH$: Sodium hydroxide
  • $Ca(OH)_2$: Calcium hydroxide
  • $Al(OH)_3$: Aluminum hydroxide
  • $NH_4OH$: Ammonium hydroxide (polyatomic ion + hydroxide)

Chemical Formulas for Acids

• Identify Hydrogen: All acids contain hydrogen atoms that are donor.
• Determine Type: Binary (e.g., $HCl$) or oxoacid (e.g., $H<em>2SO</em>4$)?
• Balance Formula: Match oxidation states for a neutral compound.
• Verify Structure: Ensure correct bonding and molecular arrangement.

Chemical Formulas for Bases

• Hydroxide Group (OH-): Foundation of Arrhenius bases.
• Metal Cation: Provides positive charge to balance hydroxide.
• Charge Balance: Match cation and hydroxide charges.
  Example: For $Ca^{2+}$ two hydroxides $OH^-$ needed: $Ca(OH)_2$.

Physical Properties of Acids

• Sour Taste: Acids have a sour taste; e.g., citric acid in lemons.
• React with Metals: Acids react with active metals to produce hydrogen gas.
• Conduct Electricity: Aqueous solutions conduct current.
• Low pH Values: Registered below 7; strong acids approach 0.

Physical Properties of Bases

• Color Changes: Bases turn red litmus paper blue.
• Slippery Feel: Bases feel slippery; found in soap.
• High pH Values: Registered above 7; strong bases approach 14.

Chemical Reactions of Acids and Bases

• Neutralization Reaction: $Acid + Base \rightarrow Salt + Water$
• Color Changes: Indicators show acid-base reactions visually.
• Salt Formation: Ionic compounds result from neutralization.
• Importance: Acid-base reactions are fundamental in chemistry, explaining many natural phenomena and industrial processes.