Wiki Page, CHEM 109 General Chemistry I 41650: Lecture 31 Materials

Wiki Page
2020-11-05T14:50:47-08:00

Learn about the largest elephant toothpaste experiment ever....

The exothermic reaction of "elephant toothpaste" An iodide "catalyst" is used in this reaction and makes the conversion of hydrogen peroxide to water and oxygen gas occur very quickly!! Soap in the mixture together with the oxygen gas makes the foam. If the energy required to break the H₂O2 bonds is less than the energy given off from forming H₂O and O₂ then the reaction will be exothermic. This is the case and you can see that the enthalpy of reaction is -196 kJ/mol!

In this lecture you will learn about exceptions to the octet rule. Remember, the octet rule is a human made rule that attemps to categorize what is observed in nature! Consequently, it's not perfect- some atoms, like boron and beryllium, are stable with fewer than 8 electrons around them and others, like phosphorous and sulfur, can exist with more than 8 electrons around them! We will also talk about bond length, strength, and the energy required to break chemical bonds, just like for the elephant toothpaste reaction.

Lecture 31 Materials:

Chapter 8 Slides (Slides 28-36)

Practice Problems

Lecture 31 Attendance/Comprehension Quiz

Videos:

Practice Problems

Practice Problems KEY