An element whose $IUPAC$ name is ununtrium $(Uut)$ belongs to

$Assertion :$ Nitrogen and oxygen are the main components in the atmosphere but these do not react to form oxides of nitrogen.
$Reason :$ The reaction between nitrogen and oxygen requires high temperature.

Which of the following statements about white phosphorus is false?

Give the preparation of phosphorus trichloride and phosphorus pentachloride.

$Fe$ is made passive by

Which colorless gas has a smell like rotten fish?