The number of protons in an atom of krypton is 36.
Step-by-step explanation:
The number written above the symbol of Kr in the periodic table represents the atomic number of the element . Then the number written in the below represents the mass number.
So the mass number of krypton is 84 and the atomic number of krypton is 36. As it is known that number of protons and electrons will be equal in a stable element. Thus, the krypton atom will be having 36 protons.