Screencast 26.1
www.youtube.com/watch?v=jJFkom86-xs
This screencast walks you through the calculation of ΔHr for the decomposition of Group 1 peroxides.

Screencast 26.2
www.youtube.com/watch?v=vWZnrayWZJM
This screencast walks you through the calculation of the enthalpy change of formation of Li3N.

Screencast 26.3
www.youtube.com/watch?v=3sUQ6c4ajqE
This screencast walks you through the factors involved in the solubility of Group 1 salts.

Screencast 26.4
www.youtube.com/watch?v=sfsb_N6w-ng
This screencast walks you through the explanation of why magnesium(I) chloride does not exist.