Final answer:
Unable to provide the exact quantity of yellow paint required without additional context or ratio related to the 9 teaspoons of red paint, as the provided reference information is not relevant to the question.
Step-by-step explanation:
The question, "How much yellow paint is required when there are 9 teaspoons of red paint?" seems to be missing a key piece of information that would link the amount of yellow paint to the red paint. Without a ratio or a specific formula, we cannot determine the amount of yellow paint needed based solely on the given quantity of red paint.
However, in the provided reference information, there is no mention of a relationship between red and yellow paint. The references concern chemical indicators and their color changes at various pH values, which suggests the subject might have originally come from a Chemistry context. These references are not relevant to determining amounts of paint.
The measure of 19 contained in the graduated buret with yellow dye also does not indicate a standard ratio or formula for combining paint colors.
Therefore, without additional context or information specifying the relationship between amounts of different colored paints, we cannot accurately answer the question about the yellow paint quantity.