Unit 1: Atomic Theory and Periodicity Review

What element does this spectrum represent?

• Boron

• Nitrogen

• Aluminum

• Phosphorus

Which peak represents the 2s subshell?

• The peak at 151 MJ/mol

• The peak at 12.1 MJ/mol

• The peak at 7.19 MJ/mol

• The peak at 1.09 MJ/mol

Which peak demonstrates the greatest attractive forces?

• The peak at 151 MJ/mol

• The peak at 12.1 MJ/mol

• The peak at 7.19 MJ/mol

• The peak at 1.09 MJ/mol

How many valence electrons does this atom have?

• 1

• 2

• 3

• 5

Why does an ion of phosphorus, P^3-, have a larger radius than a neutral atom of phosphorus?

• There is a greater Coulombic attraction between the nucleus and the electrons in P^3-.

• The core electrons in P^3- exert a weaker shielding force than those of a neutral atom.

• The nuclear charge is weaker in P^3- than it is in P.

• The electrons in P^3- have greater Coulombic repulsion than those in neutral atom.

Which neutral atom of the following elements would have the most unpaired electrons?

• Titanium (Ti)

• Manganese (Mn)

• Nickel (Ni)

• Zinc (Zn)

Answer explanation

Actually model the orbital diagram - you do not need to do every subshell

Which element will have a higher electronegativity value: chlorine or bromine? Why?

• Chlorine, because it has less Coulombic repulsion among its electrons

• Bromine, because it has more protons

• Chlorine, because it is smaller

• Bromine, because it is larger

Which of the following elements has it highest energy subshell completely full?

• Sodium (Na)

• Alumnium (Al)

• Chlorine (Cl)

• Zinc (Zn)

Answer explanation

Write out the electron configuration... highest full sublevel is in parenthesis

Na - 1s²2s²2p⁶3s¹ (2p)

Cl - 1s²2s²2p⁶3s²3p⁵ (3s)

Al - 1s²2s²2p⁶3s²3p¹ (3s)

Zn- 1s²2s²2p⁶3s²3p⁶4s²3d¹⁰ (3d)

Which of the following isoelectric species has the smallest radius?

• S^2-

• Cl^-

• Ar

• K⁺

What is most likely electron configuration for a sodium ion in its ground state?

• 1s²2s²2p⁵

• 1s²2s²2p⁶

• 1s²2s²2p⁶3s¹

• 1s²2s²2p⁵3s²