Objective: To discover why mustard has a characteristic yellow color.
Eye dropper or pipette
Clear plastic cup
Safety Precautions: Perform this experiment only under adult supervision. Wear safety goggles. Ammonia is very poisonous. Do NOT eat the mustard after adding ammonia. Do not smell or inhale ammonia fumes. Do this in a well ventilated area.
1) Pour a little mustard in the clear cup. the amount is not crucial
2) Add ammonia drops until you note a color change
3) Add vinegar drops until the mustard returns to its original color.
4) Do NOT ear the mustard. Dispose by pouring all down the drain.
Few people are aware that mustard is yellow due to an additive. If you read the ingredients on the label of mustard container, it will list turmeric as an ingredients. Turmeric is derived from the root of a plant grown in the East Indies, and is used to dye mustard yellow. It is also an excellent base indicator, turning red in the presence of a base. Sine ammonia is basic, mustard will therefore turn red when ammonia is added. When vinegar is added, the ammonia is neutralized, and the turmeric will return to its yellow color.
Turmeric is used to impart the yellow color to goldenrod paper, which also turns red when ammonia or another basic solution is added.