Periodic Trends

Question 1

What is shielding effect?

Answer 1

It decribes the decreasing attrations between nucleus and an electron

Question 2

What is the pull from protons called?

Answer 2

Electromagnetic attraction

Question 3

Why are VE the easiest to be moved away?

Answer 3

Inner electrons shield them from most of the attraction

Question 4

In the Zeff equation, what are the variable and what do they mean?

Answer 4

Z = the positive attraction from nucleus (# of protons) and S = the shielding effect

Question 5

What is slaters rule?

Answer 5

It’s basically the Zeff equation

Question 6

How does shielding effect differ?

Answer 6

It’s 1 for electrons in a lower energy shell, 0.85 for electrons in the same energy shell but lower subshell, and 0.35 for electrons in the same energy shell and subshell

Question 7

What is the ionic radii of a positive ion?

Answer 7

The radii decreases as there is now a higher Zeff, same Z less S

Question 8

What is the ionic radii of a negative ion?

Answer 8

The radii increase as there is now a smaller Zeff, same Z more S

Question 9

What is the definition of ionization energy?

Answer 9

It’s the energy required to remove the high energy electrons from a gaseous atom

Question 10

What happens during ionization?

Answer 10

Energy is required to remove the electron - IT’S ENDOTHERMIC

Question 11

Ionization energy values are?

Answer 11

Postive

Question 12

What is the trend with ionization energy?

Answer 12

Across periods it increases and down groups it decreases

Question 13

So why does group 15 have a slightly higher IE than group 16?

Answer 13

Look at electron configuration
Group 16 contains one more electron, creating a less favorable arrangement (Group 15’s electron arrangement is more stable)

Question 14

What is the definition of electronegativity?

Answer 14

The tendency of an atom to attract shared electrons to itself during a chemical bond

Question 15

What is the trend of electronegativity?

Answer 15

It increases going across the periods and decreases going down a group

Question 16

What three elements do not form bond?

Answer 16

He, Ne, and Ar SO THEY DO NOT HAVE AN EN value

Question 17

What is the definition of electron affinity?

Answer 17

The energy change when as electron is added to an atom to make a negative ion

Question 18

What is the charge of EA?

Answer 18

Negative - energy is released IT’S EXOTHERMIC

Question 19

What about the EN values for noble gases?

Answer 19

Its very unstable, and it requires an energy input (It’s endothermic)