Hard to find Goldenrod paper is coated with a dye (from your kitchen) that acts as an acid-base indicator. In fact it's the world's largest acid/base indicator strip and can be used in many classroom science experiments.

Goldenrod paper turns bright red when in contact with bases (ammonia, sodium bicarbonate, washing soda) and back to its normal golden color when in contact with acids (vinegar, lemon juice, etc.)  

Each sheet is 21.6 x 27.9 cm in size (American letter size).
Teach:  Acid / base indication. Test household items (soaps, milk, juice, drinks, food) to determine if they are acidic or alkaline (basic).
Age: 5+

The indicated price is for a pack of 10 sheets. 

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