Question

what observation are made when the potassium metal are added to cold water.

Answer 1

Since potassium is highly reactive metal so when it react with cold water then reaction occur in two steps.
firstly,
2K+H20 ------->K20+H2
THEN,
K20 +2H20 -------->2KOH +H2
so final product will be potassium hydroxide.