Question

atomic radius
as you move across a period, the atomic radius ____________ because ____________
as you move down a group, the atomic radius ____________ because ____________
ionization energy
as you move across a period, the ionization energy ____________ because ____________
as you move down a group, the ionization energy ____________ because ____________
ionic size
cations (+) are always ____________ than the atoms they come from because ____________
anions (-) are always ____________ than the atoms they come from because ____________
ionic radius
as you move across a period, the ionic radius ____________ because ____________
as you move down a group, the ionic radius ____________ because ____________
electronegativity
as you move across a period, the electronegativity ____________ because ____________
as you move down a group, the electronegativity ____________ because ____________

Explanation:

• Atomic Radius:
• Across a period: Decreases. As protons increase (same energy level), nuclear charge pulls electrons closer.
• Down a group: Increases. New energy levels added, electrons are farther from nucleus.
• Ionization Energy:
• Across a period: Increases. Higher nuclear charge (same energy level) makes it harder to remove electrons.
• Down a group: Decreases. Electrons in higher energy levels are more shielded, easier to remove.
• Ionic Size:
• Cations: Smaller. Lose electrons, less electron - electron repulsion, same nuclear charge pulls remaining electrons closer.
• Anions: Larger. Gain electrons, more electron - electron repulsion, electrons spread out.
• Ionic Radius:
• Across a period: Decreases (for cations then anions with a jump). Similar to atomic radius trends but with ion - specific electron changes.
• Down a group: Increases. New energy levels added.
• Electronegativity:
• Across a period: Increases. Higher nuclear charge (same energy level) attracts bonding electrons more.
• Down a group: Decreases. Electrons in higher energy levels are more shielded, less attraction for bonding electrons.

Answer:

• Atomic Radius:
• Across a period: Decreases; because protons increase (same energy level), nuclear charge pulls electrons closer.
• Down a group: Increases; because new energy levels added, electrons are farther from nucleus.
• Ionization Energy:
• Across a period: Increases; because higher nuclear charge (same energy level) makes it harder to remove electrons.
• Down a group: Decreases; because electrons in higher energy levels are more shielded, easier to remove.
• Ionic Size:
• Cations: Smaller; because lose electrons, less electron - electron repulsion, same nuclear charge pulls remaining electrons closer.
• Anions: Larger; because gain electrons, more electron - electron repulsion, electrons spread out.
• Ionic Radius:
• Across a period: Decreases (for cations then anions with a jump); because similar to atomic radius trends but with ion - specific electron changes.
• Down a group: Increases; because new energy levels added.
• Electronegativity:
• Across a period: Increases; because higher nuclear charge (same energy level) attracts bonding electrons more.
• Down a group: Decreases; because electrons in higher energy levels are more shielded, less attraction for bonding electrons.