pH Indicators

pH indicators are substances that change color depending on the acidity or alkalinity of a solution. They help determine the pH level, which measures how acidic or basic a liquid is on a scale from 0 to 14. For example, vinegar (acidic) turns a different color than soap (basic). These indicators are useful in chemistry, biology, and environmental testing to quickly assess the nature of a solution without complicated equipment. Common examples include litmus paper and phenolphthalein, both providing visual cues to understand the solution's pH.