Chapter 5

Question 1

What is the length of each period determined by?

Answer 1

By the number of electrons that can occupy the sublevels being filled in that period.

Question 2

What is the period of an element determined by?

Answer 2

Element’s highest occupied main energy level.

Question 3

What is the unit for energy level?

Answer 3

n

Question 4

What is a period?

Answer 4

Highest occupied energy level.

Question 5

What is Block in the periodic table?

Answer 5

The last ending sublevel.

Question 6

What are groups in the periodic table?

Answer 6

The total number of electrons in highest energy level.

Question 7

How do you identify an element in S block?

Answer 7

By the electron number in the last S subshell.

Question 8

How do you identify an element in D-Block?

Answer 8

It is identified by the number of electrons in the last S subshell plus the sub shell.

S subshell + D subshell.

Question 9

How do you identify an element in P block?

Answer 9

It is identified by:
(S+P) +10

Question 10

State some periodic properties that show clear periodic trends.

Answer 10

1) Atomic radius
2) electronegativity
3) ionic radii
4) ionization energy
5) Valence electrons
6) Electron affinity

Question 11

What is Atomic radii?

Answer 11

One half the distance between the nuclei of identical atoms that are bonded together.

Question 12

What is the periodic trend of atomic radius across a period?

Answer 12

As we move from left to right in a period atomic radius decreases.

Question 13

Why does atomic radius decrease as you move from left to right in a period?

Answer 13

Because the atomic number in the elements increase some nuclear charge, increase the number of shells and elements remain the same.

Question 14

What is ionization energy?

Answer 14

The amount of energy required to rule an electron from a neutral atom which forms an ion.

Question 15

What is ionization energy measured in?

Answer 15

kJ/mol

Question 16

What is the equation for ionization energy?

Answer 16

X + first ionization energy = X+ + e–

Question 17

Ionization energies of the main group elements _____ across each period.

Answer 17

Increase.

Question 18

Among the main group elements, ionization energies _____ down the groups.

Answer 18

Decrease

Question 19

What is an ion?

Answer 19

An atom of bonded atoms that has a positive or negative charge.

Question 20

How does an ion get its charge?

Answer 20

By having a number of electrons unequal to that of its protons.

Question 21

Explain the term first ionization energy.

Answer 21

It refers to the ionization energy required to remove a neutral atom’s first electron. Giving an ion a single positive charge.

Question 22

Explain the term second ionization energy.

Answer 22

The amount of energy required to remove a second electron from one positive ion. Giving an ion 2 positive charges.

Question 23

What is electron affinity?

Answer 23

The energy change that happens when an electron is acquired by a neutral atom.

Question 24

What is the equation for electron affinity?

Answer 24

A + e⸌ + energy = A⸌

Question 25

What are some trends of electron affinity?

Answer 25

-Electron affinity increases from going left to right of the periodic table in a period. -electron affinity decreases across the group from top to bottom.

Question 26

Electron affinity increases from going left to right of the periodic table in a period. When does this periodic trend have an exception?

Answer 26

It happens in the case of Carbon and nitrogen, Carbon has a greater electron affinity than nitrogen because nitrogen has more stable filled valence shell electron configuration.

Question 27

Electron affinity increases from going left to right of the periodic table in a period. When does this periodic trend have an exception?

Answer 27

It happens in the case of Carbon and nitrogen, Carbon has a greater electron affinity than nitrogen because nitrogen has more stable filled valence shell electron configuration.

Question 28

What are valence electrons?

Answer 28

The electrons involved in forming chemical compounds.

Question 29

Electronegativity ______ across each period.

Answer 29

______ and ______ are the last electronegative elements.

Question 30

Do compounds have atoms of low attraction or high attraction?

Answer 30

Low attraction.

Question 31

What are the most electronegative elements?

Answer 31

Nitrogen, oxygen and halogens.

Question 32

How does electronegativity tend to change down a group?

Answer 32

Decreases or remains the same.

Question 33

What is unusual about noble gases, and how does their electronegativity compare when they form compounds?

Answer 33

Some noble gases don't form compounds, but when they do, their electronegativity is high or similar to halogens.