high school chemistry

Drinking Dinosaur Pee?!

It has been claimed that because all water ultimately ends up in the water cycle, we drink water that the dinosaurs peed out. What does chemistry have to say about this assertion?

Unit Cells and Layer Sequences using Dimpled Packaging

Regularly dimpled trays such as those used in food packaging can be used to represent layers of atoms in solid structures. For example, the square array of dimples in transparent plastic mini quiche trays can be used to depict layers within cubic or tetragonal unit cells. Multiple solid structures and ways to represent those structures are described. 

Chemical Activities Involving Reversible Thermochromic Pigments

The color of a thermochromic system depends on its temperature. The colors of leuco dye-based systems can also be influenced by adding acids or bases to the thermochromic reactions. These can be used to create colorful demonstrations of acid-base chemistry. Thermochromism found in color changing cups can also be used to visualize heat flow, and therefore thermodynamic principles, associated with stretching and contracting elastomers.