1. Show the class pictures of five very different mammals, such as a cat, kangaroo, horse, rabbit, and monkey. Explain that all these animals are mammals, and that mammals constitute one class of the animal kingdom, which also includes other classes, such as reptiles, birds, and fish. Ask students what these five mammals have in common and mark their responses on a sheet of chart paper.
When ionic compounds are in a molten state or dissolved in water, forming an aqueous solution, the ions that formed the ionic compounds are able to move around freely, thus able to conduct electricity.
are brittle and cannot be deformed (ions in lattice not free to slide over each other) Solids do not conduct electricity (electrons are tightly bound to ions) In aqueous solution, or when melted to a liquid, ionic compounds do conduct electricity (ions are now free to move). This is often an identifying feature of an ionic solid.