Acids and Bases: Definitions

• Acids: Substances that release hydrogen ions (H⁺) when dissolved in water.
• Bases: Substances that release hydroxide ions (OH⁻) when dissolved in water.

Common Properties

• Electrolytes: Both acids and bases can conduct electricity in aqueous solutions because they dissociate into ions.
• Taste:
  • Acids have a sour taste (e.g., citric acid in lemon).
  • Bases have a bitter taste and a slippery feel (e.g., soap).
• Indicator Reactions:
  • Litmus Paper: Acids turn blue litmus paper red; bases turn red litmus paper blue.
  • pH Scale: Both acids and bases can be measured on the pH scale, with acids below 7 and bases above 7.

Neutralization Reaction

• When acids and bases react together, they undergo a neutralization reaction, forming water and a salt.
• General Equation: Acid + Base → Salt + Water

Ionization in Water

• Acids ionize in water to produce H⁺ ions.
• Bases ionize in water to produce OH⁻ ions.
• Both acids and bases affect the concentration of these ions in water, influencing the solution’s pH.

Corrosiveness

• Both acids and bases can be corrosive, meaning they can cause damage to materials and tissues.

Role in Chemical Reactions

• Acids and bases are commonly involved in chemical reactions, including acid-base reactions, which are essential in various biological and industrial processes.

Presence in Everyday Life

• Acids are found in foods (e.g., vinegar, citrus fruits), while bases are found in cleaning products (e.g., baking soda, soap).

Brønsted-Lowry Theory

• According to this theory:
  • Acid: A substance that can donate a proton (H⁺).
  • Base: A substance that can accept a proton (H⁺).

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