Properties of Chemical Bonds

Bond Properties

Why do atoms Combine?

●Realize Chemical Formulas show:

○The elements in a compound

○The ratio of their elements

Chemical Bonds

●Are strong attractive forces between atoms or ions in a molecule or
compound which are formed by

○Unstable electrons where atoms are gaining or losing electrons

●The goal is Stability

○Atoms want to be neutral and following the Octet Rule (octet =8)

○They want a full outer shell (valence shell)

○Stability drives all bond formation.

Multiple Choice

Which is an electron?

• A
• B
• C

Multiple Choice

This is a Bohr Diagram of Aluminum. How many valence electrons does Aluminum have?

• 3

• 4

• 5

Multiple Choice

How many valence electrons does Tin (Sn) have?

• 8

• 7

• 5

• 4

Multiple Choice

How many valence electrons does Lithium (Li) have?

• 8

• 1

• 5

• 2

Multiple Choice

How many valence electrons does Bromine (Br) have?

• 5

• 6

• 7

• 8

Multiple Choice

What is a valence electron?

• an electron that is found in the outermost shell of an atom. 
• an electron found in the innermost shell of an atom.
• an electron found in the middle shell.

Multiple Choice

Which element is this?

• Nickel

• Neon

• Sodium

• Nitrogen

Multiple Choice

Name this element.

• Argon

• Chlorine

• Aluminum

• Boron

Multiple Choice

Name this element.

• Neon

• Magnesium

• Sodium

• Manganese

Multiple Choice

How many valence electrons?

• 2

• 3

• 4

• 5

Types of Chemical Bonds

➔

There are 3 types of chemical bonds

--Covalent
--Ionic
--Metallic

Covalent Bonds and Properties

Bonds are
Between

Valence
Electrons

Are:

Bonds
Break:

State(s) of

Matter:

AKA:

2 anions (nonmetals)

Shared

Very easily

Liquids or
gases

Molecules

Multiple Choice

Covalent bonds are between...

• Metal and Non-metal
• Non-metal and Non-metal
• Metal and Metal

Multiple Choice

How do covalent bonds form?

• Donating & receiving valence e- between atoms.
• Opposite slight charges attract each other between compounds.
• Scientists are still not sure how they form.
• Sharing valence e- between atoms.

Multiple Choice

Which of the following is NOT formed by a covalent bond?

• K₂S
• H₂O
• I₂
• CO₂

Multiple Choice

Is hydrogen considered a metal or a non-metal?

• A metal
• Nonmetal
• Metalloid

Ionic Bonds and Properties

Bonds

are

Between

Valence
Electrons

Are:

Bonds
Break:

Can

Conduct

State(s)
of Matter:

AKA:

Cation
and an
anion (metal and nonmetal)

Transferred

Quite
difficult to
break

Electricity

Solids (as
a crystal)

Compoun
ds

Multiple Choice

Ionic bonds form between two ions that have...

• ionic compounds
• negative charges
• positive charges
• opposite charges

Multiple Choice

When an atom loses a valence electron, it becomes a(n) _________ion.

• positive 
• negative

Multiple Choice

In order to have a stable arrangement of 8 valence electrons, metal atoms are likely to _________electrons.

• gain
• lose

Multiple Choice

Because the force of attraction between the positive and negative ions is so strong, ionic compounds have _________ melting points.

• high
• low

Metallic Bonds and Properties

Bonds

are

Between

Valence
Electrons

Are:

Bonds
Break:

Can

Conduct:

State(s)
of Matter:

AKA:

2 cations (metals)

Mutually
shared
(equal)

Extremely
Difficult

Electricity

Solids

Alloys or
Metals

Multiple Choice

Which of the following is NOT a property of metals?

• Hard

• Can conduct electricity

• Very brittle (breaks easily)

• Malleable (can bend without breaking)

Multiple Choice

What do electrons do in a metallic bond?

• They stay on the metal atom.

• They are transferred from atom to atom.

• They form a covalent bond with another atom.

• They float around freely.

Multiple Choice

Which of the following would be held together by the metallic bond?

• Atoms of iron (Fe)

• Molecules of CH₄

• Atoms of sulfur (S)

• Units of NaCl

Multiple Choice

What does malleable mean?

• Breaks easily

• Always stays in the same shape

• Can be drawn into wires

• Can be forced into a certain shape without breaking

Chemical Formulas

●The formulas show:

○The elements in a compound/molecule

○The ratio of their elements

Chemical Bonds

●

Strong attractive forces between isotopes or ions in a molecule or compound

●

Formed by:

○Gaining electrons (electron affinity/ionization energy)

○Losing electrons (electronegativity)

Stability

●

Octet Rule
○Most atoms form bonds in order to have 8 valence electrons

○Full outer energy levels

○Want to be like Noble Gases
■A charge of 0

○Stability drives all bonding

Write this down in your notes!

• Know the difference between what happens with anions and cations.

• Cations are positive because they need to lose electrons to reach stability

• Anions are negative because they need to gain electrons to reach stability
  

Cations vs. Anions

Look in your Salmon colored packet, they are on the Periodic Table!

Look inside the element square, bottom right corner

Where are the charges?

Multiple Choice

According to the Octet Rule, atoms of elements react with each other in order to attain ____ electrons in their outermost energy level or shell.

• 2

• 4

• 6

• 8

• 10

Multiple Choice

Which of the following elements LOSES 1 electron in order to attain an octet?

• potassium

• calcium

• helium

• boron

• fluorine

Multiple Choice

Which of the following elements GAINS 1 electron in order to attain an octet?

• sodium

• calcium

• helium

• boron

• chlorine

Multiple Choice

Which of the following elements LOSES 2 electrons in order to attain an octet?

• lithium

• magnesium

• helium

• sulfur

• bromine

Multiple Choice

Which of the following elements GAINS 2 electrons in order to attain an octet?

• cesium

• magnesium

• phosphorus

• sulfur

• iodine

Multiple Choice

Which of the following elements LOSES 3 electrons in order to attain an octet?

• nitrogen

• lithium

• aluminum

• oxygen

• iodine

Multiple Choice

Which of the following elements can EITHER GAIN or LOSE 4 electrons in order to attain an octet?

• silicon

• beryllium

• boron

• selenium

• chlorine

​

Complete the table on page 3

Open Ended

Why do electronegativities decrease down each group?

Open Ended

State and explain the trend in electronegativity across period 3 from Na to Cl.

Open Ended

State the meaning of the term electronegativity.

Draw

Draw the electronegativity trend in the periodic table below.

Multiple Choice

Which has the largest E.N. ?

• N

• O

• C

• B

Multiple Choice

Which element has the largest E.N. ?

• S

• Te

• Rb

• Cs

Multiple Choice

Which element has the smallest E.N. ?

• Mg

• Be

• Sr

• Ba

Multiple Choice

Which shows increasing E.N. ?

• F, Cl, Br, I

• Cl, Si, Al, Na

• Ba Mg, Cl, F

• O, Se, K, Rb

How does ELECTRONEGATIVITY play a role?

• DEN Range is the difference in electronegativity values between atoms

• Determines the type of bond, based on the difference calculated

• Covalent bonds have similar electronegativities

• Ionic bonds have different electronegativities

• This is done without looking at whether element is anion/cation.

​

Complete the table on page 4