Step 4: Summarize nuclear changes. a) Use your completed table and models to write a summary that addresses the following questions:
1. How does energy change in these reactions? Is energy needed to start the reactions or is
energy given off in the reactions? For each type of reaction, approximately how much
energy is released?
**see attached

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.

in cartography, a contour line (often just called a "contour") joins points of equal elevation (height) above a given level, such as mean sea level. a contour map is a map illustrated with contour lines, for example a topographic map, which thus shows valleys and hills, and the steepness or gentleness of slopes.

explanation: