Acids and Bases

Definition of Acids and Alkalis

• Acids are substances that release hydrogen ions (H+) when dissolved in water.
• Alkalis are substances that release hydroxide ions (OH-) when dissolved in water.

pH Scale

• The pH scale is a measure of the acidity or basicity of a solution.
• The pH scale ranges from 0 to 14, with 7 being neutral.
• Solutions with a pH less than 7 are considered acidic, while solutions with a pH greater than 7 are considered alkaline (basic).

Neutralization Reaction

• Neutralization occurs when an acid reacts with an alkali to form a salt and water.
• The general equation for a neutralization reaction is: Acid + Alkali → Salt + Water

Indicators

• Indicators are substances that change color in the presence of acids or alkalis.
• Common indicators include litmus, phenolphthalein, and universal indicator solution.
• Indicators can be used to determine the pH of a solution and identify whether it is acidic, neutral, or alkaline.