Hydrogen combines directly with

A chalcogen combines directly with hydrogen with great difficulty to form a hydride. This chalcogen also burns in air to form a solid polymeric dioxide and has got the highest electrical resistance amongst metals. The chalcogen is

At high temperature nitrogen can combine directly with:

Which element does not combine directly with nitrogen at high temperatures?

Which of the following metals do not combine directly with hydrogen gas to form hydride?

Name the alkali metals which do not combine directly with nitrogen.

Which of the following elements combines directly with nitrogen to form its nitride ?