Periodic trends - Shielding / effective nuclear charge only

The concept of shielding happens because of

• attraction between nucleus and valence electrons
• attraction between nucleus and core electrons
• repulsion between valence electrons and other valence electrons
• repulsion between core electrons and valence electrons

How many SHIELDING electrons are there in this atom? 1s² 2s²2p⁶

• 2
• 4
• 6
• 8

How many SHIELDING electrons are there in this atom?
1s² 2s²2p⁶ 3s²3p⁶ 4s²

• 2
• 4
• 10
• 18

Shielding electrons are: 

• Electrons in the highest energy level
• Electrons in the lower energy levels
• Electrons that just come and go - they don't stay with the atom
• Electrons that are excited

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Valence electrons are: 

• Electrons in the highest energy level
• Electrons closest to the nucleus
• Electrons that just come and go - they don't stay with the atom
• Electrons that are excited

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Shielding electrons causes the force of attraction to the nucleus to 

• increase
• decrease

Tags

NGSS.HS-PS1-3

The effective nuclear charge is _____ the actual nuclear charge

• the same as
• less than
• greater than

Tags

NGSS.HS-PS1-8

When a new energy level is added to the atom, shielding

• increases
• decreases

In moving from left to right across a period on the periodic table, the effective nuclear charge

• increases
• decreases
• stays the same

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

In moving from top to bottom down a group on the periodic table,

• shielding increases
• shielding decreases