an indicator paper that turns red in an acid and blue in a base
litmus paper
The paper you are describing is known as universal indicator paper. It is a type of paper that is commonly used in chemistry to determine the acidity or basicity of a solution. The paper is impregnated with a mixture of several different pH indicators that, when exposed to a solution, will change color depending on the pH of the solution.
When the paper comes in contact with an acid, it will turn a shade of red that corresponds to the strength of the acid. The stronger the acid, the more vivid the red color will be. On the other hand, when the paper is exposed to a base, it will turn a shade of blue or green, depending on the strength of the base. The stronger the base, the more intense the blue or green color will be.
It is important to note that universal indicator paper is only a qualitative indicator of pH and cannot be used to determine the exact pH value of a solution. For more precise measurements, a pH meter or pH indicator solution would be required.
More Answers:
Understanding Neutralization Reactions: Formation of Water and Salt from Acid-Base ReactionsThe Importance of Understanding the pH Scale: Applications in Science, Biology, and Environmental Studies
Understanding the pH Scale: An Introduction to Acids and Bases