Because tooth paste is a base because anything that turns a blue or green when mixed with red cabbage juice(indicator) is a base.
brown:)
Green
blue-pinky colour.
Reversible
I've never heard of it changing color when it is cooled, but it does change color with pH, and can be used as an indicator for acids and bases.See the Web Links for more information about using cabbage color as a pH indicator.
Red cabbage juice will turn pink when an acid is added to it. Due to the acids in a carbonated drink, 7up till turn the juice a pink colour.
When adding tomato juice to cabbage juice, the cabbage juice turns redish
green
Green
Blue/green color
blue-pinky colour.
As tea ranges from mildly to strongly acidic, the cabbage juice should turn red or pinkish.
The color change, though physical by itself, is caused by a chemical change of some colored substances in cabbage.
reversable
Basic colour of C.J. is purple blue
Reversible
pink
no it reacts only with rainbow cabbage juice and not red