1.7: Coulomb's Law and Periodic Trends

Question 1

Effective Nuclear Charge Trend

Answer 1

-increases across a period
-no change down a group

Question 2

Atomic Radius Trend

Answer 2

-decreases across a period
-nuclear charge increases, electrons are added to the same energy level so no increase in distance
-increases down a group
-nuclear charge increases, no increase in effective nuclear
charge
-valence electrons occupy an additional energy level,
increases r^2

Question 3

Ionization Energy Trend

Answer 3

-increases across a period
-effective nuclear charge increases, no change in r^2
-increase in force of attraction
-decreases down a group
-increase in nuclear charge, no increase in effective
nuclear charge
-r^2 increases, decrease in force of attraction

Question 4

Electron Affinity Trend

Answer 4

-generally increases across a period
-increase in force of attraction, decrease radii, and
increase in ionization energy makes it easier for the atom to gain an electron and more energy is released
-generally decreases down a group
-nuclear charge increases but no r^2 difference
-decrease in force of attraction and less energy released when electron is added

Question 5

Electronegativity Trend

Answer 5

-increases across a period
-increase in force of attraction, attracts bond electrons
-decreases down a group
-overall decrease in force of attraction, bonded electrons
included