Alright! Ever heard of a molecule that can't decide if it's ionic or covalent? Meet magnesium iodide! This dude's a bit of a mix.

• Fun Fact: In magnesium iodide, ∆χ (difference in electronegativity) = 1.4.
• What's χ? It stands for electronegativity, and magnesium iodide has a value of χ = 2.0.
• Drama Alert: This means both its ionic and covalent characters are around 50%. It's like being half Gryffindor and half Slytherin!

⚡ Because of this dual character, magnesium iodide has an extraordinarily high lattice enthalpy. Think of this like a super strong bond that's super hard to break - like the friendship between Harry, Ron, and Hermione!

Models are like those recipes we try to follow. Sometimes, we end up making something a bit different than expected!

• Theory: When we talk about lattice enthalpy for an ionic compound, we assume it’s completely ionic.
• Reality: But, big plot twist! If bonds between ions have some covalent character, the real (or experimental) lattice enthalpy is often way higher than what we predict.

🍿 Popcorn Fact: This surprise is common with larger ions, especially those with low electronegativity values. Why? Their electron clouds can be easily distorted (or "polarised"). This means they can kinda share electrons (like sharing popcorn in a movie) – that's covalent bonding - on top of their ionic bonding.