1f-1h Chemical bonds Edexcel

Ionic Bond - an ionic bond exists when a metal loses electrons to a nonmetal.

​This causes the metal to become charged positively while the nonmetal to have a negative charge. These opposite charges are not attracted to each other like magnets. ​

​Bonding Basics

Covalent Bond - an covalent bond exists when a two nonmetals (both seeking more electrons) share some of their valence electrons to make both elements happy.

​Bonding Basics

Multiple Choice

A(n) ______________ bond forms when electrons are transferred while a(n) _____________ bond forms when electrons are shared.

• Covalent, Ionic

• Ionic, Covalent

• Covalent, Radioactive

• Radioactive, Ionic

Multiple Choice

Which compound below is formed from an ionic bond?

• CO₂

• MgCl₂

• NO₂

• H₂O

Multiple Choice

Which compound below is formed from a covalent bond?

• CO₂

• MgCl₂

• Na₂O

• SrO

IONIC BONDING

In this Unit we will place most of our emphasis on ionic bonds. More specifically how we determine their formulas and the proper nomenclature used to identify them.

Multiple Choice

Which is most likely to form a negative ion...

• an element from Group 7

• a metal
• an element from Group 1
• an element with atoms that have eight valence electrons

Multiple Choice

Which of the following is the correct formula for an ionic bond between magnesium and bromine?

• MgBr

• Mg₂Br

• MgBr₂

• BrMg₂

• BrMg

Multiple Select

What are the properties of ionic compounds?

• low melting and boiling point

• high melting and boiling point

• can conduct electricity in aqueous solution

• poor electrical conductor in liquid form

Properties of Ionic Compounds

• high melting and boiling point

• can conduct electricity when they are dissolved in water

• hard, rigid, and brittle

• generally soluble in water

• form crystals

Multiple Choice

Ionic compounds conduct electricity when dissolved in water. Which statement below best explains the property?

• Ions are free to move.

• Electrons are free to move.

• Bonds are strong.

• There are weak intermolecular forces of attraction.

Multiple Choice

Why do ionic compounds have high melting and boiling points?

• Their ions are free to move.

• Their ions are held in fixed positions.

• They have many strong bonds which require a large amount of heat energy to overcome these strong bonds.

• They have weak bonds which require a little amount of heat energy to overcome these weak bonds.

Multiple Select

Which three of the following are features of ionic compounds? (click 3 boxes)

• They have bonds between metals and non-metals.

• They have bonds between two non-metals.

• They form simple molecular structures.

• They form giant ionic lattices.

• They involve the transfer of electrons.

Multiple Select

Be and F can combine to form BeF₂, an ionic compound. Select ALL the true statements.

• Each Be atom loses two electrons from the outer shell.

• Each F atom gains two electrons from Be.

• The force holding the ionic compound together is electrostatic attraction.

• Each F ion has a charge of -1

Multiple Select

Select all the true statements:

• Each outer shell electron in Cl is represented by a cross.

• In Na, the total charge is -2.

• Na+ and Cl- are held together by electrostatic attraction.

• Na+ has a full outer shell of electrons.

Match

Match the following to form true statements:

• When solid, ionic compounds

• When melted ionic compounds

• Ionic compounds have

• There are many strong bonds

• Elements in group 1 of the periodic table form ions

cannot conduct electricity

can conduct electricity

high melting and high boiling points

between ions in an ionic compound.

with a charge of 1+

• cannot conduct electricity

• can conduct electricity

• high melting and high boiling points

• between ions in an ionic compound.

• with a charge of 1+

Sharing is Caring!

C3.5 - Covalent Bonding

Multiple Choice

Covalent bonds are formed between...

• two or more metal atoms

• two or more non-metal atoms

• a metal and a non-metal atom

Multiple Choice

The diagram shows the electron dot/cross diagram for phosphorous trichloride. Which one of the following best describes the bonds?

• 3 single bonds

• 3 double bonds

• 1 single and 2 double bonds

• 2 single and 1 double bond

Multiple Choice

Which one of the following is the correct Lewis structure for the nitrogen molecule (N₂)?

• A

• B

• C

• D

Fill in the Blank

In covalent bonding, atoms of non-metals _____ electrons between them.

Multiple Choice

How many electrons are shared in a double bond?

• 2
• 4
• 6
• 8

Multiple Choice

How many electrons should Carbon have around its Lewis dot structure?

• 1
• 3
• 4
• 5

Multiple Choice

Which of the following is the correct Lewis dot structure for the molecule fluorine (F₂)?

• A
• B
• C
• D

Multiple Choice

Identify structure shown as simple covalent or other.

• Simple covalent

• Other

Multiple Choice

Identify the simple covalent structure.

• A

• B

• C

• D

Multiple Choice

Identify physical properties of the simple covalent compounds shown.

i. low melting point

ii. conducts electricity when solid

iii. always soft

• i only

• i, ii and iii

• iii only

• i and iii only

Multiple Select

Select the properties of simple covalent substances.

• Low melting and boiling points.

• High melting and boiling points.

• Do not conduct electricity.

• Good conductors of electricity.

Multiple Choice

Why do simple covalent substances not conduct electricity?

• They have low melting points.

• They have low boiling points.

• There are no delocalised electrons or free ions to carry the charge.

• The molecules are too large.

Multiple Choice

Covalent structures have low melting and boiling points because it does not take much energy to break the _____ intermolecular forces.

• weak

• strong

Giant Covalent Structure

Multiple Choice

Why is diamond strong?

• It's made of carbon

• It doesn't conduct electricity

• It forms 4 strong covalent bonds

• So it can cut glass

Multiple Choice

What structure is shown in the diagram?

• Diamond

• Graphite

• Carbon fiber

• Carbon nanotubes

Multiple Choice

What element are diamond and graphite made up of?

• Sodium

• Carbon dioxide

• Carbon

• Silicon

Multiple Choice

Why does graphite conduct electricity?

• Ions are free to move to carry the charge

• Atoms can move

• Free electrons that can carry the charge

Multiple Choice

Formulae of these might include H₂O each molecule contains 1 O and 2H atoms

• simple covalent molecules

• metallic

• giant covalent

• ionic

Multiple Choice

Melting points are very high – a large amount of energy is needed to break all the covalent bonds.

• simple covalent molecules

• metallic

• giant covalent

• ionic

Multiple Choice

Low melting and boiling points which increase with increasing molecule size due to increased intermolecular forces.

• simple covalent molecules

• metallic

• giant covalent

• ionic

Multiple Choice

Which answer shows the correct number of C-C covalent bonds in its allotropes?

• Diamond 3, Graphite 3

• Diamond 4, Graphite 3

• Diamond 3, Graphite 4

• Diamond 4, Graphite 4

Multiple Choice

Silicon (IV) oxide has properties that similar to graphite.

• TRUE

• FALSE

Buckminsterfullerene

• This is the first fullerene discovered, which is C-60.

• This molecule has the shape of a football.

• The carbon atoms are arranges at the corners of 20 hexagons and 12 pentagons.

Properties of Buckminsterfullerene

• Low sublimation point. This is because there are weak Van der Waals’ forces in between each of this molecule and no continuous layered giant structure as in graphite.

• It’s relatively soft because it doesn’t require much energy to overcome the weak intermolecular force.

• It’s a poor conductor of electricity because the extent of electron decolisation is lower.

Multiple Choice

Which can conduct electricity ?

• diamond

• graphite

• both

• neither

Multiple Choice

Which carbon structure is used as a lubricant because it is slippery ?

Multiple Choice

Why is graphite so soft and slippery?

• its layers are weakly attracted to each other

• It is made of small molecules

• It has electrons that are free to move

• each carbon has 4 bonds

• it has a low melting point

Multiple Choice

What structure is shown in the diagram?

• Diamond
• Graphite
• fullerene

Multiple Choice

Which of the following is true about C₆₀ ?

• Each carbon bonded covalently to 3 other carbon atoms in a hexagonal ball like structure
• Each carbon bonded covelently to 4 other carbon atoms in layers
• a giant lattice structure
• pentagonal in shape

Multiple Choice

Two forms of carbon are described:

A. has a melting point of 4000^oC and conducts electricity when solid.

B. has a melting point of 280^oC and does not conduct electricity.

What are the names of these two forms of carbon?

• A. diamond

  B. graphite

• A. diamond

  B. fullerene C₆₀

• C. graphite

  B. fullerene C₆₀

• A. graphite

  B. diamond

Multiple Choice

Carbon dioxide, CO₂, is a gas at room temperature but silicon dioxide, SiO_2, is a high melting point solid.

What is the explanation for this.

• the inter-molecular forces in CO₂ are weaker than the inter-molecular forces in SiO₂

• the inter-molecular forces in CO₂ are weaker than the covalent bonds in SiO₂

• the covalent bonds in CO₂ are weaker than the covalent bonds in SiO₂

• the covalent bonds in CO₂ are weaker than the ionic bonds in SiO₂

Multiple Choice

I am a solid that does not conduct electricity.

My melting point is 560^oC

When molten I do conduct electricity

What type of structure and bonding do I have?

• giant ionic

• giant covalent

• molecular ionic

• molecular covalent

Multiple Choice

I am a gas at room temperature.

What kind of structure and bonding do I have ?

• giant ionic

• giant covalent

• molecular ionic

• molecular covalent

Multiple Choice

I have a melting point of 1600^oC

I do not conduct electricity in any state.

what type of structure and bonding do I have?

• giant ionic

• giant covalent

• molecular ionic

• molecular covalent

Metallic Bonds

sea of electrons

Definition

Metallic bonding is the strong attraction between closely packed positive metal ions and a 'sea' of delocalised electrons.

Properties of metallic bonds

• Once the metal atom loses electrons they move randomly

Properties of metallic bonds

• If you apply an electric current the electrons can carry the charge through the solid metal.

• Metallic bonds CAN conduct electricity

Properties of metallic bonds

• Atoms are arranged in a regular arrangement

• Once hit they can therefore move

• This is why metals are MALLEABLE

• Metals are also DUCTILE

Multiple Choice

Metallic bonds are held together by...

• The attraction of positive and negative ions

• Sharing electrons

• The attraction of positive ions to a sea of delocalised electrons

• Tranfer of electrons