SolutionsAccepting and Releasing Electrons
1. Ions
What is an ion? Which ions do sodium and chlorine form when they react?
An electrically charged atom (or molecule), because it has lost or gained electrons. Sodium gives up an electron and forms the Na+ cation; chlorine accepts it and forms the Cl− anion.
2. Hard to melt
Why do ionic compounds, such as common salt, have such high melting points?
Because ions of opposite charge attract each other with very strong electrostatic forces. A lot of energy is needed to separate them and melt the solid.