Question

This chart lists four elements from the periodic table.

A 2-column table with 4 rows labeled elements from the periodic table. The first column labeled name of element has entries calcium, gold, argon, iodine. The second column labeled classification has entries metal, metal, noble gas, nonmetal.
Atoms from which two elements would form ionic bonds?

calcium and gold
gold and argon
argon and iodine
iodine and calcium

Answer 1

Iodine and calcium.

Calcium is a metal (tends to lose electrons) and iodine is a nonmetal (tends to gain electrons), so they form an ionic compound (Ca2+ and I−, formula CaI2).