CC5,6,7- bonding Flashcards
how can you tell which group (column) an element is in?
the number of electrons in the outer shell
how can you tell which period (row) an element is in?
the number of shells the element has
What are isotopes?
Atoms of the same element that have different numbers of neutrons
how do you calculate relative atomic mass?
(% of isotope 1 x mass of isotope 1) + (% of isotope 2 x mass of isotope 2) / 100
give an example of ionic bonding
sodium chloride, NaCl (salt)
what happens when sodium and chlorine bond?
The sodium has one electron on its outer shell, which is transferred to the chlorine atom. This gives both a full outer shell, and the sodium becomes positively charged, while the chlorine has a negative charge.
what is an ion?
a charged atom
How do ions become charged
by gaining or losing NEGATIVLEY CHARGED electrons
properties of ionic compounds (7)
- giant lattice structure
- attraction between + and - ions
- conduct electricity when molten/ disolved in water
- electrons can move
- high melting and boiling point
- electrostatic attraction
- between a metal and non-metal
what is electrostatic attraction?
when oppositely charged ions are attracted to each other - non contact force.
What is covalent bonding?
bonding between non-metals, atoms gain a full outer shell of electrons by sharing pairs of electrons
properties of covalent compounds?
- simple structure
- low melting and boiling points due to weak intermolecular forces of attraction
- never conducts electricity - electrons have no charge
- between nonmetals
properties of metallic bonds
- conduct electricity
- strong giant structure
- bonding between metals
- high melting and boiling points
- malleable - layers can move past eachother
how do metallic compounds conduct electricity if theyre solids?
the have delocalised electrons that can move within the structure
What is an allotrope?
Different forms of the same element
What are the allotropes of carbon?
diamond, graphite, graphene
what are some physical properties of diamond?
- hard
- high melting point
- insoluable in water
- doesn’t conduct electricity
- used in cutting tools
what are some physical properties of graphite?
- slippery (used a a lubricant)
- brittle
- insoluble in water
- conducts electricity
describe the structure of graphene?
giant covalent
type of fullerene
joined in hexagons
1 atom thick
conducts electricity well
4th electron can move
describe the structure of graphite?
-layered
-every 4th electron is delocalised therefore can conduct electricity
-each carbon atom covalently bonded to 3 others
-weak imfoa, layers can slide past each other or be left behind when friction is applied
describe the structure of diamond
giant covalent structure
strong bonds between all atoms
each carbon atom bonded to 4 others
very strong
What are polymers?
Long chains of monomers joined together
fullerenes (5)
- molecules of carbon shaped in tubes or balls
- made up of C atoms arranged in hexagons/ pentagons/ heptagons
- simple structure
- useful for transporting medicines around body
- large SA good catalyst
buckminsterfullerenes
- molecular formula C60
- hollow sphere of 20hex and 12pent
- stable molecule
- forms soft brown/black crystals
nano-tubes
- fullerenes
- light
- 1 atom thick
- strong structure
- conduct electricity
what are nonotubes used in
- strengthen materials w/o adding weight
- robust, used in tennis rackets
examples of some covalent compounds
water
carbon dioxide
methane
what are giant covalent structures
- all atoms bonded by strong covalent bonds
- high mp and bp, lots of energy needed to break the bonds
- don’t conduct electricity (no charged particles
What is an ionic bond
- The electrostatic forces of attraction between oppositely charged particles
- The bond is formed when atoms lose or gain electrons in order to achieve a full outer shell
