Periodic Trends
Atomic and Ionization Radius
Electronegativity and Reactivity
Coulombic Attraction and Effective Nuclear Charge
Practice Problems
100

What element has the smallest atomic radii? 

Fluorine 

100

What is a cation? And what ionic radius comes from this compared to the neutral atom?

Cation - when a positively charged ion is formed when a metallic element loses an electron.


It is smaller than a neutral. 

100

Electronegativity is defined as an atom's ability to do this in a chemical bond. 

Attract electrons. 

100

Describe what happens to the attractive force as the effective nuclear charge increases.

It gets stronger.

When the (Zeff) increases, so does the force of attraction.

100

Which of the following elements has the highest first ionization energy?

A) Na

B) Mg

C) Ai

D) O

Oxygen

200

As you move down a group, what happens to the atomic size? 

Increases in atomic size.

200

What group forms the smallest cations, having the highest ionization energies?

Noble Gases

200

Describe what would happen to the attractive force as the distance between charged particles increases and decreases.

It decreases as it gets further away and strengthens as it gets closer

200

"The net positive charge felt by an electron in a multi-electron atom, taking into account both the nuclear charge and shielding."

Is what?

Effective nuclear charge. 

200

This element has the highest electronegativity of all elements.

Fluorine 

300

This trend in atomic sizes happens as you move across a period from left to right.

Decrease in atomic size. 

300

What is an anion and what is the size comparison when it gains an electron compared to a neutral atom? 

Anion - A negatively charged ion has more electrons than protons. 

It is larger. (Pull is not as tight.)

300

This group of elements is known for having the highest reactivity due to their single valence electron. 

Alkali Metals

300

As you move down a group, Zeff increases slightly, BUT the increase is offset by this factor:

Increased shielding from inner electrons. 

The shielding electrons "shield" the outer shell electrons from being attracted to the nucleus. 

300

Which atom has the lower ionization energy?

A. N, O

B. Te, Sn 

C. Ne, F 

A. O

B. Sn

C. F

400

Reactivity for nonmetals AND metals increase/decrease down a group. Answer both. 

Nonmetals - Decreases 

Metals - Increases

400

When ions have the same number of electrons, the ion with the highest atomic number will have what type of ionic radius?

The smallest ionic radius. 

400

The elements located in group 17 are highly reactive because they readily gain an electron to complete their valence shell.

Halogens.

400

The coulombic attraction between an electron and the nucleus becomes weaker when this happens.

Increased electron shielding.

400

The alkali metals are most likely to form these types of Ions.

Cation with +1 charge  

600

This trend occurs due to the increasing number of protons across a period, BUT the shielding effect remains relatively consistent. This results in a stronger attraction between nucleus and the valence electrons.

What is this trend?

Effective nuclear charge (Zeff)

600

Which has the larger radius:

Cl- or F- 

And why? 

Cl- Chlorine has more electron shells than fluorine, making it have a larger ionic radius.

600

Which element has a higher electronegativity?

(O) or (S)?

Oxygen, because it is higher in the periodic table and across to the right. 

600

In a multi-electron atom, which would experience a stronger coulombic attraction: an electron in the 1s orbital, or an electron in the 3p orbital, and why?

1s electron, because it is closer to the nucleus and experiences less electron shielding. 

600

Which of the following groups of elements are arranged in order of increasing first ionization energy?


A. B, C, Al, Si 

B. Al, B, Si, C

C. Al, Si, B, C

D. Si, B, Al, C


C. Carbon is the largest because it will be the hardest to extract electrons.