Question

why potassium reacts vigorously with cold water while copper does not react with water or steam?​

Answer 1

Because pottasium is a highly reactive metal So it reacts vigorously with even cold water .

And copper is less reactive metal so it doesn't react with even steam .

Hope it helps .....

Answer 2

Potassium is a highly reactive metal which when exposed to air or water reacts virgorously producing a large amount of heat. Whereas in case of copper which is less reactive doesn’t show any reaction