Visual models are really helpful for understanding the differences between ionic and covalent bonds, especially when we look at how atoms are structured. Here are some ways these models make things clearer:

1. How Electrons Move:

   • Ionic bonds happen when one atom gives away its electrons to another atom.
     For example, sodium (Na) has 11 electrons. It loses one electron to become stable, turning into Na$^+$.
     We can show this with a simple equation:
     • Na ⇌ Na$^+$ + e$^-$
   • On the other hand, covalent bonds are formed when atoms share electrons.
     A great example of this is water (H$_2$O). Here, each hydrogen atom shares its electrons with the oxygen atom.
     We often show this with Lewis dot structures.

2. Understanding Crystal and Molecule Shapes:

   • Ionic compounds usually create a crystal lattice structure.
     For example, in sodium chloride (NaCl), the Na$^+$ and Cl$^-$ ions are arranged in a repeating pattern.
     This formation gives it a high melting point, around 801°C.
   • In contrast, covalent compounds like methane (CH$_4$) can be shown with ball-and-stick models, which help us see the tetrahedral shape made by sharing electrons.

3. Energy Changes:

   • Visual models can also show us how energy changes when bonds are formed.
     Ionic bonds release a lot of energy during their formation.
     For instance, magnesium oxide (MgO) has a very high lattice energy, sometimes over 800 kJ/mol.
   • Covalent bonds do release energy too, but usually less for each bond.
     For example, a C–H bond in methane gives off about 412 kJ/mol.

4. Different Physical Properties:

   • Using visual models, we can compare things like how well substances conduct electricity and dissolve in water.
     Ionic compounds normally dissolve in water and conduct electricity when they do.
     In contrast, covalent compounds don’t usually conduct electricity and their solubility can change based on how polar they are.

In summary, visual models really help students understand ionic and covalent bonds. They make it easier to see how electrons are transferred or shared, how structures are arranged, and how energy and physical properties work. This knowledge is important for 11th-grade chemistry.