pH Scale, Acids, and Bases

The pH scale is a measure of how acidic or basic a substance is, ranging from 0 (very acidic) to 14 (very basic), with 7 being neutral.

A pH less than 7 indicates that a substance is acidic.

A pH greater than 7 indicates that a substance is basic (alkaline).

An acid is a substance that donates protons (H+) in a solution and has a pH less than 7.

A base is a substance that accepts protons (H+) or donates hydroxide ions (OH-) in a solution and has a pH greater than 7.

A neutral solution has a pH of 7, meaning it is neither acidic nor basic.

Litmus paper is used to test the acidity or basicity of a solution; blue litmus paper turns red in acidic solutions, while red litmus paper turns blue in basic solutions.

Mixing equal amounts of H+ and OH- ions creates a neutral solution.

Hydrochloric acid (HCl) is a strong acid commonly found in gastric acid and has a pH less than 1.

An example of a weak acid is acetic acid, which is found in vinegar and has a pH around 2-3.