Question

1. which element would have the lowest ionization energy?

• a. barium (ba)
• b. magnesium (mg)
• c. tellurium (te)
• d. oxygen (o)

1. why do noble gases not have electronegativity values?

• a. they are too reactive
• b. their electronegativity is too high to measure
• c. they do not need additional electrons
• d. they have no valence electrons

1. the trend for ionization energy across the periodic table is:

• a. increases from top to bottom, decreases from left to right
• b. decreases from top to bottom, decreases from left to right
• c. increases from top to bottom, increases from left to right
• d. decreases from top to bottom, increases from left to right

1. which statement about metallic character is correct?

• a. metallic character increases as ionization energy increases
• b. metallic character decreases as you move down a group
• c. metallic character increases as you move from right to left across a period
• d. metallic character increases as electronegativity increases

Explanation:

• Question 4: Ionization energy decreases down a group. Barium (Ba) is in Group 2, lower than Magnesium (Mg). Tellurium (Te) is a non - metal in Group 16 and Oxygen (O) is also a non - metal in Group 16. Non - metals generally have higher ionization energies than metals in lower groups.
• Question 5: Noble gases have a full valence shell (except Helium which has 2 valence electrons). They do not need additional electrons, so the concept of electronegativity (tendency to attract electrons) is not applicable.
• Question 6: Ionization energy decreases down a group (top to bottom) because the outermost electrons are further from the nucleus. It increases across a period (left to right) as the nuclear charge increases and the atomic radius decreases.
• Question 7: Metallic character increases as you move down a group and from right to left across a period. Metallic character is inversely related to ionization energy (lower ionization energy, more metallic).

Answer:

• 4. A. Barium (Ba)
• 5. C. They do not need additional electrons
• 6. D. Decreases from top to bottom, increases from left to right
• 7. C. Metallic character increases as you move from right to left across a period