Chapter 9 homework
9.50 Write the full electron configurations for each element.
a. N 1𝑠 2 2𝑠 2 2𝑝3
b. Mg 1𝑠 2 2𝑠 2 2𝑝6 3𝑠 2
c. Ar 1𝑠 2 2𝑠 2 2𝑝6 3𝑠 2 3𝑝6
d. Se 1𝑠 2 2𝑠 2 2𝑝6 3𝑠 2 3𝑝6 4𝑠 2 3𝑑10 4𝑝4
9.54 Write electron configurations for each element. Use the symbol of the previous noble gas in
brackets to represent the core electrons.
a. Te [𝐾𝑟]5𝑠 2 4𝑑10 5𝑝4
b. Br [𝐾𝑟]4𝑠 2 3𝑑10 4𝑝5
c. I [𝐾𝑟]5𝑠 2 4𝑑10 5𝑝5
d. Cs [𝑋𝑒]6𝑠1
9.62 How many valence electrons are in each element?
a.
b.
c.
d.
Ba - 2, it’s in row 2A
Al – 3, it’s in row 3A
Be – 2, it’s in row 2A
Se - 6, it’s in row 6A