What type of bond exists between an element X with atomic number 12 and Y with atomic number 17?

Step 1. Identify the elements:

• X has atomic number 12 → Magnesium (\(\ce{Mg}\)), a metal in Group 2.
• Y has atomic number 17 → Chlorine (\(\ce{Cl}\)), a non-metal in Group 17.

Step 2. Bonding behavior:

• Magnesium loses 2 electrons to form \(\ce{Mg^{2+}}\).
• Each chlorine atom gains 1 electron to form \(\ce{Cl^-}\).
• Thus, magnesium combines with 2 chlorines → \(\ce{MgCl2}\).

Step 3. Bond type: This transfer of electrons from a metal to a non-metal forms an electrovalent (ionic) bond.

Final Answer: Electrovalent (ionic)