Use the list to answer the question.

potassium, Group IA
calcium, Group IIA
iodine, Group VIIA
neon, Group VIIIA

Which two elements in the list would bond together based on their ionic charges?

potassium and iodine
potassium and neon
calcium and potassium
calcium and neon

1 answer

To determine which two elements would bond together based on their ionic charges, we need to understand the common ionic charges of the elements listed:

  • Potassium (K) is in Group IA and typically has a charge of +1.
  • Calcium (Ca) is in Group IIA and typically has a charge of +2.
  • Iodine (I) is in Group VIIA and typically has a charge of -1.
  • Neon (Ne) is in Group VIIIA and is a noble gas, which means it typically does not form bonds.

In ionic bonding, a positively charged ion (cation) will bond with a negatively charged ion (anion) to form a stable compound.

Based on the charges:

  • Potassium (+1) can bond with Iodine (-1) to form potassium iodide (KI).
  • Calcium (+2) does not have a counterpart in the list that provides a -2 charge, but if paired with iodine, it could still form a bond as calcium can bond with two iodine atoms (CaI2).
  • Neon does not typically bond due to its full valence shell.

From the list of pairs provided, the best option that forms a bond based on their ionic charges is:

potassium and iodine.