Paper 1 Corrections Flashcards
How would you describe metallic bonding and its forces?
Metal Cations surrounded by delocalised electrons. Strong forces of attraction between cations and electrons
NOT INTERMOLECULAR
How do you obtain pure, dry crystalls from solution?
Filter
Heat in water bath untill crystallisation starts to occur ( to concentrate solution)
Allow to cool and dry crystals between filter papers
What does it mean when atom economy is 100%?
All atoms in reactants are present in the product
What may cause an atom economy of below 100%
Incomplete / reversible reactions
Competing / side reactions
Practical losses during experiment
What are carbon allotropes and what are 3 examples?
Structures of carbon atoms bonded by single covalent bonds (strong)
Diamond, Graphene, Fullerene
What is Diamond’s structure?
Giant covalent (structure/lattice)
-> Continuous
Each carbon atom bonded to 4 others
What is Graphene’s structure?
Giant covalent (structure/lattice)
-> Continuous
Each carbon atom bonded to 3 others
What is fullerene’s structure
Simple Molecular
-> Multiple seperate molecules
Each carbon atom joined to 3 others
Giant Covalent
What are the melting/boiling points like for Diamond and Graphene
- Lots of energy needed
- Generally strong materials
Many strong covalent bonds need to be broken
Simple molecular
What is the melting/boiling point of Fullerenes like?
- Less energy needed
- Low (er) boiling pint
Only need to break weak forces between molecules
the bigger the fullerene = more inmf
Does diamond conduct electricity?
NO
- No free electrons to carry charge - no conduction
Does Graphene conduct electricity?
YES
- Each carbon atom has one free electron
-> Delocalised = conduction
Do fullerenes conduct electricity?
They only conduct across the individual surfaces of fullerenes
-> No Electron movement between molecules = poor conductor
Why may some titration readings be excluded from the mean?
Inprecise burette readings
Not concordant with other results
What are the reasons for electroplating metals
improves the appearance/ shiny
improves resistance to corrosion/
prevents oxidation
can make e.g. ‘gold’ object more cheaply
using a gold layer on a cheaper base / looks
more expensive than it is (1)
Definition of isotope
atoms with same
number of protons but different
number of neutrons
Why may phytoextraction be better than extracting from ore?
decontaminates ground / conserves
{nickel / nickel ores / ores} / allows use
of low-grade ore /
specified environmental reason: e.g.
less noise due to mining / carbon
neutral / less carbon dioxide
If you shift equilibrium towards forward reaction for bromine test what would be observed?
Orange would go PALER as MORE bromine is used up
What do you say about non rusting metals?
They are RESISTANT to corrosion
