C3 Structure And Bonding Flashcards
Do opposite charges attract or repel
Attract
Why are metals alloyed
To increase strentgh
Intermolecular force
The force that arise between the molecules of a substance
What boiling, melting point do molecules have
Low
Ionic lattice
lattice is formed as ions attract each other and form a pattern
Why ionic compounds have a high melting point
Large amounts of energy needed to break the many strong bonds
Double bond in diatomic molecule
Forms between a carbon atom and an oxygen atom
When do ionic compounds conduct electricity
When molten or dissolved in water
Examples of small molecules which contain covalent bonds
Nitogen
Water
Ammonia
How covalent bond forms
When pairs of electrons are shared by atoms
How size of molecule affect boiling melting points
Larger molecules have higher boiling and melting points
Substances that would have weak intermolecular forces
Gases, liquids or low melting point solids
How double and triple covalent bonds formed
When more than one pair of electrons are shared between the atoms for a full outer shell
How surface area to volume increases as particle size reduces
Decreasing the length of a cube by 100 increases its surface area by 100
Can nanoparticles be used in sun cream
Yes
Uses of nanoparticles
Drug delivery
Diagnostic
Tissue engineering
Advantages of using nanoparticles
Lower costs
Produce stronger and lighter wind turbines
Can save energy
Disadvantages of using nanoparticles
Lung inflammation
Heart problems
Why nanotechnology research should continue
Can change dental medicine, healthcare and human life
How to classify a particle as a coarse, fine or nanoparticles
1 x 10 and 2.5 x 10
-5 -6
Coarse - 10 10
-7 -6
Fine - 10 10
Describe, with an example, how a Group 1 metal atom becomes a positive ion
+
Lithium loses 1 electron to become Li
Factors that affect rate of evaporation
Temperature
Surface area
Wind speed
Charges of ion group 1,2,6,7
Group 1 = +1
Group 2 - +2
Group 6 = -2
Group 7 = -1
How unfamiliar elements become ions
Metal atoms lose electrons to form cations
Non-metal atoms tend to gain electrons and form anions
How the position of an element on the periodic table relates to the charge on its most stable monatomic ion
Elements often form anions with negative charge
Ratio of metal and non-metal ions in compounds
2:1
Why substances have different melting and boiling points from each other
The stronger the forces between particles, the higher its melting and boiling points
Properties of diamond
Hard in nature
Molecules closely packed
No prescence of free carbon atoms
Properties of graphite
High melting and boiling points
Good electrical conductivity
Softness
Physical properties of fullerenes
Behaviour depends on temperature
Physical properties of metals
Malleable
Ductile
Good conductors of heat and electricity
Structure of pure metal
Giant metallic structure
Do giant covalent structure have high or low melting point
High
Describe relationship between graphite and graphene
Graphene is one single layer of graphite
Explain the structure of fullerenes
Hexagonal rings of carbon atoms joined by covalent bonds
Use for graphite
Used in pencils, lamps, batteries
Use for diamonds
Embedded into saw blades
Drill bits
Grinding wheels
How metals form giant structures
The outer shell electrons become delocalised and surround the positive metal ions
Why small molecules don’t conduct electricity
Small molecules have no overall electric charge
Why ionic compounds conduct electricity in molten state
Ions break free to move and can conduct electricity
Process of melting
Molecules of a solid speed up enough that the motion overcomes the attraction so molecules can move past each other as a liquid
Process of boiling
A liquid turns into vapour when heated to its boiling point
Process of condensing
Water vapour in the air is changed into liquid water
