4.2.4 The pH scale and neutralization

• What is the pH of a neutral solution?

  7
• What is the pH range for acidic solutions?

  0-6
• What is an example of an acidic solution?

  Lemon juice
• What are the products of a neutralization reaction?

  Salt and water
• What happens when hydrochloric acid (HCl) reacts with sodium hydroxide (NaOH)?

  NaCl and H₂O
• Neutralization reactions occur in everyday applications such as adjusting soil pH
• Hydrochloric acid reacts with sodium hydroxide to form sodium chloride and water.


  True
• A pH value of 7 indicates acidity.

  False
• A pH greater than 7 indicates alkalinity.

  True
• What is the range of the pH scale?

  0 to 14
• Acids have a pH less than 7.


  True
• Steps in a neutralization reaction:

  1️⃣ Acid reacts with a base

  2️⃣ Salt is formed

  3️⃣ Water is produced
• In neutralization, salt is formed from the cation of the base and the anion of the acid.
• The pH scale ranges from 0 to 14
• Arrange the acidity or alkalinity of solutions based on their pH value

  1️⃣ pH 0-6: Acidic

  2️⃣ pH 7: Neutral

  3️⃣ pH 8-14: Alkaline
• Which pH value indicates a neutral solution?

  7
• Match the pH value with its acidity or alkalinity:

  pH 0-6 ↔️ Acidic

  pH 7 ↔️ Neutral

  pH 8-14 ↔️ Alkaline
• A pH value greater than 7 indicates an alkaline solution


  True
• What is the general term for the neutral compound formed in a neutralization reaction?

  Salt
• The general reaction for neutralization is: Acid + Base → Salt + Water
• The pH scale ranges from 0 to 14.
• The pH scale is used to measure the acidity or alkalinity of a solution.
• Solutions with a pH of 7 are considered acidic.

  False
• What does a pH value between 8 and 14 indicate?

  Alkalinity
• Match the substance with its approximate pH:

  Lemon juice ↔️ 2

  Water ↔️ 7

  Ammonia ↔️ 11
• Lime is used in agriculture to reduce soil acidity.


  True
• Match the application of neutralization with its purpose:

  Antacids ↔️ Neutralize stomach acid

  Lime in soil ↔️ Reduce soil acidity

  Wastewater treatment ↔️ Balance water pH
• What does the pH scale measure?

  Acidity or alkalinity
• A solution with a pH of 8 is alkaline


  True
• The pH scale ranges from 0 to 14 and measures the acidity or alkalinity
• A solution with a pH of 5 is considered acidic


  True
• Pure water has a pH of 7
• Acids release hydrogen ions (H⁺), while bases accept hydrogen ions
• Antacids are used to neutralize stomach acid


  True
• What two products are formed during a neutralization reaction?

  Salt and water
• Match the product of neutralization with its description:

  Salt ↔️ Neutral compound from ions

  Water ↔️ Formed by H⁺ and OH⁻ ions
• What does a pH less than 7 indicate?

  Acidity
• Match the pH range with its acidity or alkalinity:

  0-6 ↔️ Acidic

  7 ↔️ Neutral

  8-14 ↔️ Alkaline
• The pH scale measures the acidity or alkalinity of a solution.
• Water has a neutral pH of 7.