Bonding Flashcards
Define ionic bonding
The electrostatic attraction between oppositely charged ions
What materials does ionic bonding occur in (metal? Non metal?)
Metal with non metal
What is ionic bonding in terms of electrons?
A transfer (metals lose, non metals gain)
Why does a metal want a full outer shell?
Most stable (like noble gases) = least reactive
What’s the structure of an ionic compound?
A giant ionic lattice
With strong electrostatic forces between ions
Properties of ionic compounds
High mp + bp, solid = insulators (no free electrons), conductor when liquid (free electrons)
What’s the structure of metallic bonding?
Sea of electrons (delocalised) carry charge = conducts
Strong electrostatic forces
Layers can slide over eachother
Properties of metals
Solid at room temp, good conductors (sea of electrons), malleable ( layers slide over), shiny, ductile.
Advantages of using iron alloys (steel)
They are more corrosion resistant (stainless steel) and harder
Uses of polymers
Electrical insulation, clothing (flexible)
What is a thermosoftening polymer?
It melts when heated
Define a thermosetting polymer
Don’t melt
Can ethene or ethan polymerise?
Ethene (only alkenes)
What’s the molecule called that is a chain of linked monomers
Polymer
What sort of bonds do polymers have?
Covalent
What sorts of bonds do alkanes and alkenes have?
Covalent bonds
What is the process of making ceramics out of clay?
Moulded then Heating them an oven or kiln = hardens
How to make ceramics out of glass?
Heat glass to high temp over furnace, mould then leave to harden = Brittle
Define composite
Material made from 2 or more materials that are embedded to have different properties eg fibre glass (glass in plastic) = lower density + strong
What are 2 examples of giant covalent structures?
Graphite and diamond
Properties of diamond
A giant covalent structure: hard, high mp, doesn’t conduct,
Graphite properties
Giant covalent structure: lubricant (slide over layers), high mps, conducts due to one delocalised electron
What is graphene?
One layer of graphite, one atom thick carbon, added to materials to increase strength
What are fullerenes?
Molecules of carbon shaped as hollow tubes or sphere
Uses of fullerenes
Nanotechnology, catalysts (big SA), medical so a drug goes to perfect spot, lubricant
What are properties of nanotubes?
Conductors, stretchy and strong
Uses of fullerenes in nano technology
Strengthening materials, keep low density, electronics
Define covalent bonding
2 non metal atoms sharing electrons to make covalent bonds
How are covalent bond diagrams drawn?
H-O-H or as ven diagrams with dot and crosses
Simple molecular properties?
Weak forces of attraction between molecules, mp+bp low, don’t conduct (no free), liquid or gas due to weak forces.
What is a simple molecular substance?
A substance joined by covalent bonds that contains a few atoms, weak intermolecular forces
