[thedy]

I have tried one experiment.I put red rose to NH4OH and rose became blue.Then i put for few hours to water and rose became red again.Could you explain,why?

If I tried in SO2,will rose dye and in water get previous color?

thanks....for answer

[billnotgatez]

A Google search got this site
http://www.absoluteastronomy.com/topics/PH_indicator

with this information

Naturally occurring pH indicators
Light Mauve Hydrangea
Many plants or plant parts contain chemicals from the naturally-colored anthocyanin
Anthocyanin

Anthocyanins are solubility vacuole pigments that may appear red, purple, or blue according to pH. They belong to a parent class of molecules called flavonoids synthesized via the phenylpropanoid pathway....
 family of compounds. They are red in acidic solutions and blue in basic. Extracting anthocyanins from red cabbage
Red Cabbage

The red cabbage is a sort of cabbage, also known as Red Kraut or Blue Kraut after preparation.Its leaves are coloured dark red/purple....
 leaves or the skin of a lemon
Lemon

The lemon is the common name for Citrus limon. The reproductive tissue surrounds the seed of the angiosperm lemon tree. The lemon is used for culinary and nonculinary purposes throughout the world....
 to form a crude acid-base indicator is a popular introductory chemistry demonstration.

Anthocyanins can be extracted from a multitude of colored plants or plant parts, including from leaves (red cabbage
Cabbage

The cabbage is a leafy garden plant of the Family Brassicaceae , used as a Leaf vegetable. It is a herbaceous, biennial plant, dicotyledonous flowering plant distinguished by a short stem upon which is crowded a mass of leaves, usually green but in some varieties red or purplish, forming a characteristic compact, globular cluster .
); flowers (geranium
Pelargonium

Pelargonium is a genus of flowering plants which includes about 200 species of perennial plants, succulent plants, and shrubs, commonly known as geraniums or storksbills....
, poppy
Poppy

A poppy is any of a number of showy flowers, typically withone per Plant stem, belonging to the Papaveraceae. They include a number of attractive wildflower species with showy flowers found growing singularly or in large groups; many species are also grown in gardens....
, or rose
Rose

A rose is a perennial plant flower shrub or vine of the genus Rosa, within the family Rosaceae, that contains over 100 species and comes in a variety of colors....

[billnotgatez]

Unfortunately the original posting was back in November.
I too would have liked to see pictures of their results.