Acids, Bases, and Salts: Comprehensive Notes

Acids, Bases, and Salts

Introduction

• Acids, bases, and salts are three main categories of chemical compounds with distinct chemical properties.
• In daily life, we encounter many substances with different tastes (sour, bitter, sweet, salty).

Acids and Bases

• Acids and bases are familiar chemical compounds.
• Examples:
  • Acetic acid in vinegar
  • Citric acid in lemons
  • Magnesium hydroxide (milk of magnesia) in antacids
  • Ammonia in household cleaning products
• Hydrochloric acid is present in gastric juice and essential for digestion (1.2-1.5 L per day).
• Acids make food taste sour.
• Citric and ascorbic acid (vitamin C) contribute to the sour taste of citrus fruits.
• The word "acid" comes from the Latin word 'acere,' meaning sour.
• Different substances contain different types of acids.
• Lemon, grapefruit, and orange contain citric acid.
• Vitamin C is also known as ascorbic acid.
• Amla (gooseberry) is a rich source of vitamin C.
• Boric acid is used to wash eyes.
• Cola drinks contain carbonic acid (produced by carbon dioxide), making them fizzy.

Safety with Acids

• Acids are corrosive.
• Eye protection (safety glasses or face shield) should be worn when handling acids.

Naturally Occurring Acids

• Citric acid: Citrus fruits like lemons, oranges, and limes.
• Lactic acid: Sour milk.
• Boric acid: Volcanic eruptions, minerals, sea water.
• Formic acid: Sting of bees and ants.
• Butyric acid: Rancid butter.
• Tartaric acid: Tamarind, grapes, apples.
• Acetic acid: Vinegar.
• Oxalic acid: Tomato.
• Malic acid: Apples.
• Uric acid: Urine.
• Carbonic acid: Sea water, rain water.
• Stearic acid: Fats.

General Properties of Acids

1. Acids are sour to taste (from the latin word acidus/acere meaning sour).
2. Acids turn blue litmus solution red.