Question

why noble gases are placed in a separate group

Answer 1

Because they already have completed their octate and can stably retain without combing with other metals or non metals....

hope it helps..

Answer 2

hey mate,
here is your answer,

noble gases are placed separately because they already have complete octates ( outermost shell ) and can be stable in the environment without combing with other metals or non metals....

hope it helps..
Please mark me as brainliest...