Ionization Energy/Electronegativity Ionization energy is… how hard it is to steal an electron Electronegativity is… how good an atom is at stealing electrons Quick Write Who is harder to steal from? Atom #1 Atom #2 Probably Atom #2, because it’s holding on to its “electrons” more strongly. Ionization Energy/Electronegativity The trend for both: 1. IE/E increases across a period (LàR) IE/E decreases down a group (Top à Bottom) Increases highest Decreases ** There is one exception to this trend: The Noble Gases have 0 electronegativity. They’re not very good at stealing electrons at all. Ionization Energy/Electronegativity Second ionization energy is… how hard it is to steal a second electron always greater than first IE …but has the same trend! Example #1 Which has higher amount of ionization energy, oxygen (O) or carbon (C)? highest Example #1 Which is more electronegative, sodium or potassium? highest Example #3 What are 3 elements that have a higher ionization energy than Chlorine (Cl)? highest Which is less electronegative, Si or P? Which is less electronegative, Si or P? Answer: Si Which has a higher ionization energy, Br or F? Which has a higher ionization energy, Br or F? Answer: F What is bigger, an atom of Sc or Y? What is bigger, an atom of Sc or Y? Answer: Y Which of the following is the most electronegative? a. Al b. Mg c. S d.Rb Which of the following is the most electronegative? a. Al b. Mg c. S d.Rb Answer: S Which of the following has the lowest level of second ionization energy? a. Rb b. Sr c. Cs d.Ba Answer: Cs Which element in Group 15 would be the easiest to steal an electron from? Which element in Group 15 would be the easiest to steal an electron from? Answer: Bi Which of the following would be best at stealing electrons from other atoms? a. Ga b. Ge c. Au d. Ni Which of the following would be best at stealing electrons from other atoms? a. Ga b. Ge c. Au d. Ni Answer: Ge Rank the following in order of increasing ionization energy: Cl, K, Mg, Si Rank the following in order of increasing ionization energy: Cl, K, Mg, Si Answer: K< Mg < Si < Cl Exit Slip 3. In general, how does ionization energy vary throughout the periodic table? a. it decreases across a period from left to right, and decreases down a group from top to bottom b. it increases across a period from left to right, and increases down a group from top to bottom c. it increases across a period from left to right, and decreases down a group from top to bottom d. It decreases across a period from left to right, and increases down a group from top to bottom Exit Slip 3. In general, how does ionization energy vary throughout the periodic table? a. it decreases across a period from left to right, and decreases down a group from top to bottom b. it increases across a period from left to right, and increases down a group from top to bottom c. it increases across a period from left to right, and decreases down a group from top to bottom d. It decreases across a period from left to right, and increases down a group from top to bottom Answer: c Exit Slip 5. Which of the following correctly lists the elements in order of increasing electronegativity (least to most)? a. O < P < Al < Na b. Na < Al < P < O c. P < O < Na < Al d. Al < P < O < Na Exit Slip 5. Which of the following correctly lists the elements in order of increasing electronegativity (least to most)? a. O < P < Al < Na b. Na < Al < P < O c. P < O < Na < Al d. Al < P < O < Na Answer: b.