Which electrons are used in bonding?
Outer electrons
Group 1 metals react with what to form an ionic compound?
Non-metal
What group in the periodic table has the same electronic configuration as ions?
0 Noble Gases
Describe how a calcium ion is formed.
Loses 2 outer electrons
What is the charge on a potassium ion?
+1
How is a chloride ion formed?
Gains 1 outer shell electron
What do group 7 elements react with to form an ionic compound?
Metals
What is the charge on an oxide ion?
O2-
What is an ion?
A charged particle
What is an ionic compound?
Metal & Non-metal chemically bonded
What charge will group 1 elements form?
+1
What charge will the halogens form?
-1
What is ionic bonding?
Electrostatic attraction between ion formed by the transfer of electrons
Ionic compounds have what type of boiling and melting points? Why?
High, because they are lattice structure so ionic bonds would have to be broken
When melted or dissolved in water ionic compounds conduct electricity, why?
Ions are free to move
What is the formula of methane?
CH4
What are represented by ?
Shared pair of electrons – covalent bond
What type of bonding is found in methane?
Covalent
Why do simple molecules evaporate easily?
Weak intermolecular forces don’t need a lot of energy to break
What group of elements don’t often bond because they are unreactive?
0 – Noble Gases
What type of bonding is found in compounds with metals and non-metals?
Ionic
What type of bonding is found in C2H6?
Covalent
What type of bonding is found in potassium bromide?
Ionic
What is the formula of potassium bromide?
KBr
Explain in terms of electron transfer how potassium bromide is bonded?
1 outer electron is transferred from potassium to the bromine to form ions which attract
Draw a hydrogen molecule.
Draw a chlorine molecule
Give a dot and cross diagram for water
Draw an ammonia molecule
Give a dot and cross diagram for methane
Draw a hydrogen chloride molecule
Give a dot and cross molecule for an oxygen molecule
Is methane a simple molecular or giant covalent structure?
Simple Molecular
Is diamond a simple molecular or giant covalent structure?
Giant Covalent
In covalent compounds what happens to the electrons?
Shared
What is a covalent bond?
A pair of shared electrons
What is a double covalent bond?
2 pairs of shared electrons
Why does methane have low melting and boiling points?
The low melting point is because it only has weak intermolecular forces that need to be broken
Why do simple molecular substances not conduct electricity?
There are no free ions or electrons to move
What type of bonding is in diamond?
Giant Covalent
How many bonds does carbon make in a diamond?
4
Why does diamond have a high melting point?
Each carbon atom has 4 strong bonds to other carbons in a giant structure so a lot of energy is needed to break them.
Why is diamond hard?
Each carbon has 4 strong bonds in a giant structure
In graphite how many bonds does carbon make?
3
Why is graphite in pencils soft and slippery?
Layers are held together with weak forces so slide over each other
Why does graphite conduct electricity in electrodes?
1 electron from each carbon is free to move
Draw a labelled diagram for the bonding in metals
What is the name of the bonding in metals?
Metallic
Describe the bonding found in metals
Positive ions attracted to a sea of electrons
Why do metals conduct electricity?
Delocalised outer electrons can move
Why can metals be hammered and bent?
Layers slide over each other
What are shape memory alloys?
Alloys that change shape at different temperatures
What is the difference between a thermosoftening polymers and a thermosetting polymer?
Thermosoftening can be heated and reshaped but thermosetting would char
What size are nanoparticles?
Very small 1-100nm
Do nanoparticles have the same properties as the material in bulk?
No because of the large surface area for their volume
Give 3 uses or nanoparticles.
Sun protection
Socks with silver or tennis balls
Catalysts
