Three indicators are used in conjunction with acids and bases to create a rainbow of colors. In a basic solution, phenolphthalein is red, p-nitrophenol is yellow, and thymolphthalein is blue. These can be combined in various ways to create all the colors of the rainbow. If done correctly the students only see the acid or base being poured, which adds to the impressive display. There are enough materials to complete the demonstration 7 times. Aligned to the Next Generation Science Standards (NGSS)* Disciplinary Core Ideas: PS1.A; PS1.B Performance Expectations: MS-PS1-2 Cross Cutting Concepts: Patterns Engineering Practices: Analyzing and Interpreting Data Kit Includes: 25mL Red Indicator 25mL Orange Indicator 25mL Yellow Indicator 25mL Green Indicator 25mL Blue Indicator 25mL Violet Indicator 2 X 30mL Hydrochloric Acid, 1N 2 X 30mL Sodium Hydroxide, 1N 30mL Sodium Hydroxide Solution 6M (6N) DOT Info: Small quantity exemption 173.4 THIS PACKAGE CONFORMS TO 49 CFR 173.4 for domestic highway or rail transport only *”Next Generation Science Standards” is a registered trademark of Achieve. Neither Achieve nor the lead states and partners that developed the Next Generation Science Standards was involved in the production of, and does not endorse, this product. WARNING: This product can expose you to chemicals including Phenolphthalein/Methanol/Methyl isobutyl ketone, which are known to the State of California to cause cancer and reproductive harm. For more information go to http://www.P65Warnings.ca.gov.