Sadly not because the average weight of a banana is 118 grams and the average amount of potassium in a banana is 422 mg and that is not enough potassium for the banana to burn purple due to all of the chemicals that make up a banana
potassium permanganate is purple in colour and is used for cleaning.
When flame tested, Sodium ions range from a yellow to a bright orange flame and Potassium ions give a lilac or light purple flame. Neither the Sulphate nor the Chloride ions should have emission spectra in the visible range.
Potassium.
Potassium has a violet color in the flame test.
Purple
Someone told me it burns blue or purple.
Potassium chloride burns a Pink or Violet color. Source: http://hyperphysics.phy-astr.gsu.edu/hbase/chemical/flame.html
Potassium although sometimes it can look purple
potassium permanganate is purple in colour and is used for cleaning.
When flame tested, Sodium ions range from a yellow to a bright orange flame and Potassium ions give a lilac or light purple flame. Neither the Sulphate nor the Chloride ions should have emission spectra in the visible range.
Same color as a banana.
Potassium.
light purple
Potassium has a violet color in the flame test.
Purple
White
Purple