Which element in each of the following sets has the smallest first ionization energy, and which has the largest? (a) Li, Ba, K (b) B, Be, Cl (c) Ca, C, Cl

Verified step by step guidance

1. Step 1: Understand the concept of first ionization energy, which is the energy required to remove the outermost electron from a neutral atom in the gaseous state.
2. Step 2: Recall the periodic trend for ionization energy: it generally increases across a period (left to right) and decreases down a group (top to bottom) in the periodic table.
3. Step 3: Analyze set (a) Li, Ba, K: Identify their positions in the periodic table. Li is in Group 1, Period 2; Ba is in Group 2, Period 6; K is in Group 1, Period 4. Compare their positions to determine the trend.
4. Step 4: Analyze set (b) B, Be, Cl: Identify their positions in the periodic table. B is in Group 13, Period 2; Be is in Group 2, Period 2; Cl is in Group 17, Period 3. Compare their positions to determine the trend.
5. Step 5: Analyze set (c) Ca, C, Cl: Identify their positions in the periodic table. Ca is in Group 2, Period 4; C is in Group 14, Period 2; Cl is in Group 17, Period 3. Compare their positions to determine the trend.