Electrons, Ions, Valence Electrons Lesson

Multiple Choice

A student determined that the density of a sample of tin is 8.00 g/mL when the actual density of tin is 7.28 g/mL. What is the percent error in the student's calcuation?

• 0.72%

• 9.0%

• 9.9%

• 91%

Fill in the Blanks

Multiple Choice

The most efficient way to determine whether a reaction is an exothermic chemical reaction is to use -

(Hint: Exo = Outer; Thermic = Dealing with heat)

• An oxygen probe

• A temperature probe

• A pressure probe

• A pH probe

Monday, October 20, 2024 (Green Day)
Tuesday, October 21, 2024 (Gold Day)

Learning Intention:

I will be able to predict
properties of elements using
trends on the periodic table.

Success Criteria:

I will be able to correctly
answer questions about
periodic trends with 80%
accuracy.

Agenda

1.

Warm-Up✅

2.

Electron, Ions, and Valence Electrons Review

3.

4.

5.

Periodic Trends Lab

Periodic Trends Exit Ticket

Electrons & Atomic Number

●Very small, do not significantly contribute to atom’s
mass

●Electrons reside in the electron cloud.

●Electrons have a -1 charge.

●Atoms are neutral.

○There needs to be a +1 charge (proton) for every -1 charge (electron).

●Atomic number tells us the number of protons and the number of electrons.

Dropdown

The number of electrons ​

Select answer

from left to right across periods.



The number of electrons ​

Select answer

from top to bottom down groups.

Electrons & Energy Levels

●Scientists use mathematical models to estimate the locations of the electrons
within the electron cloud.

●Energy levels (also called electron shells) are distances from the nucleus of an atom where electrons may be found.

●Electrons fill energy levels in a certain order - from the inside out.

Electrons & Periods

●An element’s period is its number of energy levels.

●Elements within the same period have the same energy level.

●When discussing trends, we will see how increasing energy levels affect
various chemical properties.

Dropdown

Energy levels ​

Select answer

as we move left to right across periods.



Energy levels​

Select answer

as we move top to bottom down groups.

Poll

How are you feeling about your understanding of the information so far?

• Great!

• Good

• Okay

• Not so good

• Terrible

Electrons & Bohr Models

●Bohr Model is a way of modelling the location of
electrons within an atom.

●Center circle contains nucleus information
(protons & neutrons).

○Protons = Atomic Number

○Neutrons = Atomic Mass - Atomic Number,
rounded to whole number

●Each ring is an energy level, increasing from
inside to outside.

●1st Energy Level = 2 electrons, one on top, one
on bottom

●2nd Energy Level = 8 electrons

○Add one electron to each direction (top,
left, bottom, right) before adding another.

Draw

Draw a Bohr Model for Li.

Draw

Draw a Bohr Model for B.

Draw

Draw a Bohr Model for N.

Draw

Draw a Bohr Model for F.

Draw

Draw a Bohr Model for Ne.

Valence Electrons

●Valence electrons can absorb energy to move to a higher energy level. They can emit energy in the form of light.

• Valence electrons are involved in bonding.

• Valence electrons can be gained or lost to create ions.

• Octet Rule: Elements have achieved a stable configuration when they have 8 valence electrons
  
  

Multiple Choice

How many valence electrons are found in atoms of group 14?

• 4
• 3
• 14
• 16

Multiple Choice

Which group has the greatest number of valence electrons?

• 1
• 14
• 18
• 16

Multiple Choice

How many valence electrons does Nitrogen have?

• 1

• 2

• 3

• 4

• 5

Multiple Choice

How many valence electrons does Fluorine have?

• 4

• 5

• 6

• 7

• 8

Multiple Choice

Describe this element.

• Highly reactive metal
• Highly reactive nonmetal
• Stable
• Less stable non metal

Drag and Drop

​

Placeholder

are a group of stable elements.

​

Placeholder

and ​

Placeholder

are very reactive because they only need to lose/gain ​

Placeholder

electron to be stable.

Drag these tiles and drop them in the correct blank above

Noble Gases

Alkali metals

halogens

1

Alkali earth metals

Transition metals

2

3

4

5

Dropdown

The number of valence electrons ​

Select answer

as we move left to right across periods.



The number of valence electrons ​

Select answer

as we move top to bottom down groups

Electrons and Ions

Remember: Electrons have a -1 charge. Protons have a +1
charge. Atoms are neutral.

●

If an atom loses an electron, its charge increases by +1.

●

If an atom gains an electron, its charge decreases by -1.

●

We indicate charge in the upper right hand corner.

Charge = # Protons - # Electrons

Ion Trends

Remember: Elements always seek a stable configuration (8 valence electrons).

How many electrons do you think each group prefers to lose/gain?

What charge would their ions have?

Ion Trends

Remember: Elements always seek a stable configuration (8 valence electrons).

How many electrons do you think each group prefers to lose/gain?

What charge would their ions have?

+1 +2 +3 +4 -3 -2 -1

Multiple Choice

Na ionizes to a charge of _______

• +1

• +2

• -1

• -2

Multiple Choice

Be ionizes to a charge of ________.

• +1

• +2

• -1

• -2

Multiple Choice

Iodine has 7 valence electron. It will have a charge of _______

• -2

• -1

• +1

• +2

Multiple Choice

S has 6 valence electron. It will have a charge of _______

• -2

• -1

• +1

• +2

Multiple Choice

The octet rules requires

• 8 electrons in the outer shell

• a neutral atom

• 16 electrons in the outer shell

• the month of October

Multiple Choice

An atom becomes _________ when it gains electrons.

• Positive

• Negative

• Neutral

Periodic Organization

●Periodic table is organized by increasing atomic number (increasing protons, neutrons, and electrons from left to right, top to bottom)

●Groups have the same number of valence electrons, and the number of valence electrons increases left to right.

●Periods have the same number of energy levels, and the number of energy levels increases from top to bottom.

●These properties lead to the predictability of different chemical properties, by using periodic trends.