2.3 Periodic Properties of the Elements

What is the measure of the net positive charge experienced by the outermost electrons?

• Effective nuclear charge (Zeff)

• Principal quantum number

• Valence shell

• Atomic number

What causes the electron cloud to move closer and bind more tightly to the nucleus?

• Decrease in atomic number

• Increase in principal quantum number

• Effective nuclear charge (Zeff)

• Decrease in valence shell electrons

What cancels the increased positivity of the nucleus as one moves down a group?

• Decreased principal quantum number

• Increased principal quantum number

• Increased shielding by inner shell electrons

• Decreased shielding by inner shell electrons

Which group of elements tend to be most stable with eight electrons in their valence shell?

• Group VIIIA

• Group IIA

• Group IA

• Group VIIA

What is the trend for effective nuclear charge across a period?

• Increases from left to right

• Decreases from left to right

• Constant within a period

• Increases from top to bottom

What is the result of increased separation between valence electrons and the nucleus as one moves down a group?

• Increased shielding by inner shell electrons

• Decreased shielding by inner shell electrons

• Decreased electrostatic attraction

• Increased electrostatic attraction

What is the principal quantum number for the valence electrons as one moves down a group?

• Varies randomly

• Decreases by one each time

• Increases by one each time

• Remains constant

What is the outer boundary defined by the valence shell electrons?

• Electron cloud

• Protons

• Nucleus

• Neutrons

What is the measure of the number of filled principal energy levels?

• Atomic number

• Effective nuclear charge (Zeff)

• Valence shell

• Principal quantum number

What is the term for the electrostatic attraction between the valence shell electrons and the nucleus?

• Atomic number

• Valence electrons

• Effective nuclear charge (Zeff)

• Principal quantum number