Chapter 5 Lesson 2 & 3

Chapter 5

Lessons 2 & 3

Lesson 2 - Classification of Elements

Let’s ask a couple of questions

1. Why do element in the same group have

similar properties?

Let’s ask a couple of questions

1. Why do element in the same group have

similar properties?

2. Based on their electron configurations,

what are the four blocks of the periodic
table?

Fun Fact! You DON’T NEED the aufbau
diagram to determine electron configuration.

1s1

1s1

1s2

1s1

1s2

2s1 2s2

1s1

1s2

2s1 2s2

2p1 2p4 2p3 2p4 2p5 2p6

1s1

1s2

2s1 2s2

3s1 3s2

2p1 2p4 2p3 2p4 2p5 2p6

3p1 3p4 3p3 3p4 3p5 3p6

1s1

1s2

2s1 2s2

3s1 3s2

2p1 2p4 2p3 2p4 2p5 2p6

3p1 3p4 3p3 3p4 3p5 3p6

4s1 4s2

4p1 4p4 4p3 4p4 4p5 4p6

3d1 3d2 3d3 3d4 3d5 3d6 3d7 3d8 3d9 3d10

1s1

1s2

2s1 2s2

3s1 3s2

2p1 2p4 2p3 2p4 2p5 2p6

3p1 3p4 3p3 3p4 3p5 3p6

4s1 4s2

4p1 4p4 4p3 4p4 4p5 4p6

3d1 3d2 3d3 3d4 3d5 3d6 3d7 3d8 3d9 3d10

5s1 5s2 4d1 4d2 4d3 4d4 4d5 4d6 4d7 4d8 4d9 4d10 5p1 5p4 5p3 5p4 5p5 5p6

1s1

1s2

2s1 2s2

3s1 3s2

2p1 2p4 2p3 2p4 2p5 2p6

3p1 3p4 3p3 3p4 3p5 3p6

4s1 4s2

4p1 4p4 4p3 4p4 4p5 4p6

3d1 3d2 3d3 3d4 3d5 3d6 3d7 3d8 3d9 3d10

5s1 5s2

6s1 6s2

4d1 4d2 4d3 4d4 4d5 4d6 4d7 4d8 4d9 4d10 5p1 5p4 5p3 5p4 5p5 5p6

5d1 5d2 5d3 5d4 5d5 5d6 5d7 5d8 5d9 5d10 6p1 6p4 6p3 6p4 6p5 6p6

4f1 4f2 4f3 4f4 4f5 4f6 4f7 4f8 4f9 4f10 4f11 4f12 4f13 4f14

1s1

1s2

2s1 2s2

3s1 3s2

2p1 2p4 2p3 2p4 2p5 2p6

3p1 3p4 3p3 3p4 3p5 3p6

4s1 4s2

4p1 4p4 4p3 4p4 4p5 4p6

3d1 3d2 3d3 3d4 3d5 3d6 3d7 3d8 3d9 3d10

5s1 5s2

6s1 6s2

7s1 7s2

4d1 4d2 4d3 4d4 4d5 4d6 4d7 4d8 4d9 4d10 5p1 5p4 5p3 5p4 5p5 5p6

5d1 5d2 5d3 5d4 5d5 5d6 5d7 5d8 5d9 5d10 6p1 6p4 6p3 6p4 6p5 6p6

4f1 4f2 4f3 4f4 4f5 4f6 4f7 4f8 4f9 4f10 4f11 4f12 4f13 4f14

5f1 5f2 5f3 5f4 5f5 5f6 5f7 5f8 5f9 5f10 5f11 5f12 5f13 5f14

6d1 6d2 6d3 6d4 6d5 6d6 6d7 6d8 6d9 6d10

Let’s take a look at the Alkali Metals

Multiple Choice

Without using the periodic table, determine the group, period, and block of an atom with the following electron configuration:

$$\left[Ne\right]3s^2$$  

• group 3

  period 2

  block s

• group 1

  period 3

  block s

• group 2

  period 3

  block s

• group 3

  period 2

  block p

​[Ne]3s²

Multiple Choice

Without using the periodic table, determine the group, period, and block of an atom with the following electron configuration:

$$\left[He\right]2s^2$$  

• group 2

  period 2

  block s

• group 2

  period 2

  block p

• group 2

  period 3

  block p

• group 3

  period 2

  block p

​[He]2s²

Multiple Select

Which elements have the following valence electron configuration?

s²p³

• Sulfur

• Nitrogen

• Arsenic

• Bismuth

Lesson 3 - Periodic Trends

Let’s ask some questions

1. What are the period and group trends of

different properties?

Let’s ask some questions

1. What are the period and group trends of

different properties?

2. How are period and group trends in atomic

radii related to electron configuration?

There are four properties that we will look at.

1. Atomic Radius

There are four properties that we will look at.

1. Atomic Radius

2. Ionic Radius

There are four properties that we will look at.

1. Atomic Radius

2. Ionic Radius

3. Ionization Energy

There are four properties that we will look at.

1. Atomic Radius

2. Ionic Radius

3. Ionization Energy

4. Electronegativity

Atomic Radius

Atomic radius is calculated differently for
metals and nonmetals.

Atomic radius is calculated differently for
metals and nonmetals.

Metals

Atomic radius is calculated differently for
metals and nonmetals.

Metals

● Half the distance between adjacent

nuclei in a crystal

Atomic radius is calculated differently for
metals and nonmetals.

Metals

● Half the distance between adjacent

nuclei in a crystal

Nonmetals (plus a few others)

Atomic radius is calculated differently for
metals and nonmetals.

Metals

● Half the distance between adjacent

nuclei in a crystal

Nonmetals (plus a few others)

● Half the distance between nuclei of

identical atoms that are bonded
together

The trend
within a
period is
that atomic
radius
decreases
from left to
right.

The trend within a group is that atomic radius
increases from top to bottom.

The atomic radius trend we see is…

Multiple Choice

Which element has the largest atomic radius: magnesium(Mg), silicon (Si), sulfur (S), or sodium (Na)?

• Mg

• Si

• S

• Na

The atomic radius trend we see is…

IONIC RADIUS

Ionic Radius depends on how may electron
and element can gain or lose.

ION - Atom or a
bonded group of
atoms that has a
positive or
negative charge.

Each representative element either gains or
loses electrons.

Each representative element either gains or
loses electrons.

If you LOSE an electron,
you have a POSITIVE
CHARGE

Each representative element either gains or
loses electrons.

If you LOSE an electron,
you have a POSITIVE
CHARGE

The radius gets SMALLER

Each representative element either gains or
loses electrons.

If you LOSE an electron,
you have a POSITIVE
CHARGE

The radius gets SMALLER

Each representative element either gains or
loses electrons.

If you LOSE an electron,
you have a POSITIVE
CHARGE

The radius gets SMALLER

If you GAIN and electron,
you have a NEGATIVE
CHARGE

Each representative element either gains or
loses electrons.

If you LOSE an electron,
you have a POSITIVE
CHARGE

The radius gets SMALLER

If you GAIN and electron,
you have a NEGATIVE
CHARGE

The radius gets LARGER

The OCTET RULE is one of the most important
principles in chemistry.

Atoms tend to gain , lose, or share electrons
in order to acquire a full set of eight valence
electrons.

In a period, radius generally decreases as ions
become more positive.

In a group, radius generally increases from top
to bottom.

Multiple Choice

Which of the following elements has the smallest ionic radius: Chlorine (Cl), Selenium (Se), Fluorine (F), or Bromine (Br)

• Cl

• Se

• F

• Br

Multiple Choice

An element forms a negative ion when ionized. On what side of the periodic table is the element located?

• Left

• Right

Ionization Energy

Energy is required to create an ion.

IONIZATION
ENERGY

The energy
required to
remove an
electron from a
gaseous atom.

In a period, the first ionization energy
generally increases from left to right.

In a group, the first ionization energy
generally decreases from top to bottom.

Multiple Choice

Does fluorine (F) or bromine (Br) have a larger first ionization energy?

• F

• Br

Electronegativity

The electronegativity of an element is the
ability to attract electrons in a chemical bond.

Multiple Choice

Which element below is more electronegative?

potassium (K) or arsenic (As)

• K

• As

Multiple Choice

Which element below is more electronegative?

nitrogen (N) or antimony (Sb)

• N

• Sb