Acids 🧪🧪

• Hazards


  • Toxic
  • Environment Hazard
  • Corrosive
  • Flammable
  • Harmful
  • Explosive
  • Oxidising
  • Gas under pressure
  • Moderate Hazard
  • Health Hazard
• Soap is acidic
• Household acids


  • Facias
  • Toothpaste is alkaline
• Acids can react with baking powder


  To make a gas which helps cakes to rise
• Litmus paper changes colour in acid and alkali
• Universal Indicator changes colour across the pH scale
• Red cabbage indicator changes colour in acid, alkali and neutral solutions
• Acidic foods contain citric acid, ascorbic acid, ethanoic acid
• Acidic foods are not dangerous
• Safety Equipment when working with acids/alkalis


  • Safety Goggles: Wear at all times while using acids and alkalis
  • Gloves / Protective Clothing: Use when using concentrated acids or alkalis
  • Eye Wash Station: If acid gets in eyes, dilute with eye wash station
• To neutralise a substance, add an acid to an alkaline substance or an alkali to an acidic solution
• Stomach contains hydrochloric acid


  Indigestion medicines contain an alkali to help neutralise excess acid
• Bee stings are acidic, wasp stings are alkaline


  A weak alkali could help neutralise a bee sting
• Bacteria in mouth break down sugars, producing acid


  Toothpaste contains an alkali to neutralise the acid and prevent tooth decay
• Tooth development


  1. Baby born without teeth

  2. Milk teeth develop by 2-3 years old

  3. Milk teeth fall out and are replaced by permanent teeth

  4. Wisdom teeth may develop around age 17
• Tooth structure


  • Crown
  • Enamel
  • Dentine
  • Pulp
  • Root
  • Gums
  • Jaw bone
  • Nerves & cement
• How tooth decay occurs

  Bacteria feed on food, producing acid which eats into the enamel, causing decay
• How to prevent tooth decay

  • Diet low in sugar, rich in calcium, vitamin C and mineral salts
  • Regular dental visits to check for and treat decay early
  • Brushing teeth regularly to prevent plaque build-up
  • Fluoride in toothpaste/drinking water to strengthen enamel