Question

45) Rank Ca, Se, Co from the lowest to highest ionization energy.

46) Rank Te, S, and O from the lowest to the highest electronegativity.

Answer 1

45) Ca < Co < Se

46) Te < S < O

Step-by-step explanation:

These questions are talking about periodic trends. Here are some things to know about periodic trends:

Electronegativity

• how well an element attracts an electron
• increases left to right and bottom to top on the periodic table
• noble gases are not included
• fluorine is most electronegative element, Francium is least

Atomic Radius

• the distance between nuclei
• increases from right to left and top to bottom on the periodic table
• the more electronegative an element is, the smaller it's atomic radius
• Francium has the largest atomic radius while fluorine has the smallest

Ionization Energy

• the energy required to remove an electron
• directly proportional to electronegativity

Metallic Character

• how closely an element's properties match those of a metal
• directly proportional with atomic radius

Hope this helps :)