What must an element be in order to replace another element in a compound?

Consider two metallic rods mounted on insulated supports. one is neutral, the other positively charged. you bring the two rods close to each, but without contact, and briefly ground the the neutral rod by touching it with your hand. show answer correct answer what would be resulting charge (if any) on the initially neutral rod

Atomic nuclei of almost all elements consist of

During which interval are the persons represented by the graph not moving? a) 0 to 0.5 hrs b) 1.5 to 2 hrs c) 2 to 2.5 hrs d) 4.5 to 5 hrs