Answer:
K+ ion is identical to argon and the Br- ion is identical to krypton
Explanation:
Potassium atoms have 19 electrons, when they become an ion they lose an electron and now have 18 electrons. The noble gas that has 18 electrons is Argon. Bromine atoms have 35 electrons, when they become an ion they gain an electron and now have 36 electrons. The noble gas that has 36 electrons is Krypton.