AP Period Trends Quick Check

Reorder the following elements from smallest radius (On the left) to largest radius (On the right)

• Be

• Mg

• Ba

• Ca

• Sr

Answer explanation

Atomic Radii increases you move down a column as there more occupied electron shells.

More shells with electrons means a larger atom.

Organize these trends into the right categories

Groups:

(a) Decreases ↓ Group, Increase → Period

,

(b) Increases ↓ Group, Decreases → Period

• Electronegativity

• 1st Ionization Energy

• Atomic Radius

• Electron Affinity

When there is a large increase between ionization energies it is because the electron is now being removed from the ​ (a)   of the atom

• core

• valence shell

Answer explanation

A large increase in ionization energy indicates that an electron is being removed from the core of the atom, rather than the valence shell. Core electrons are more tightly bound to the nucleus, making their removal significantly more energy-intensive.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Select all of the valance electrons in this atom.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Select the correct statement from these options

• Li⁺¹ has a smaller radius that Li due to stronger Coulombic attraction between the nucleus and the outer electrons.

• Na⁺¹ has a larger radius that Na due to stronger Coulombic attraction between the nucleus and the outer electrons.

• N⁻³ has a larger radius that N due to stronger Coulombic attraction between the nucleus and the outer electrons.

• Al⁺³ has the same sized radius as Al due to having the same number of protons.

Answer explanation

Li⁺¹ has a smaller radius than Li because it has lost an electron, resulting in a stronger Coulombic attraction between the nucleus and the remaining electrons, pulling them closer.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2