Final answer:
The average binding energy of the K-shell in an atom increases with atomic number.
Step-by-step explanation:
The average binding energy of the K-shell in an atom increases with atomic number. This means that as the atomic number increases, the average binding energy per nucleon increases until it reaches about Z = 26, where it levels off, and then it slowly decreases. This can be seen in Figure 21.8.2, where the graph shows that the binding energy per nucleon increases up to Z = 26 and then starts decreasing.