Elements #X, Y, Z# are placed in the same Period of the Periodic Table. #Z# is a smaller atom than #Y#, which is a smaller atom than #X#. Which element has the LOWEST atomic number?
1 Answer
Dec 4, 2015
Element
Explanation:
Atomic size increases down a Group of the Periodic Table; but decreases across a Period. Why? Because the nuclear charge increases across the Period, while electrons are added to the same shell.
