Which of these elements is a noble gas? hydrogen (h) barium (ba) nitrogen (n) krypton (kr) bromine (br)

Answer : The correct option is krypton (Kr).

Explanation :

Noble gas : It is a group which is present at last in the periodic table and they belongs to group 18.

The general electronic configuration of noble gas is .

The noble gas contains six elements which are helium, neon, argon, krypton, xenon and radon.

According to the question,

The general electronic configuration of hydrogen is .

The general electronic configuration of barium is .

The general electronic configuration of nitrogen is .

The general electronic configuration of bromine is .

The general electronic configuration of krypton is .

Therefore, the correct answer is krypton (Kr).

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.

the correct answer would be b) volume versus temperature, because they are also directly proportional.