Bonding Flashcards
What is ionic bonding?
the electrostatic force of attraction
between oppositely charged ions formed by electron transfer.
What structure do ionic compounds have?
giant ionian lattice of alternating + and - ions
When is ionic bond stronger and the meltingpoints higher?
when the ions are smaller or have higher charges
What happens to the size of the ionic radi as you go down a group?
it is increases because there are more shells of electrons
When do ions form?
when electrons are transferred between elements that have a large difference in electronegativity (metals and non metals)
Are positive or negative ions smaller?
positive because they have lost electrons
What forces hold the ionic lattice together?
very strong electrostatic forces
What are the properties of ionic bonding?
-very high melting point
-soluble in h20
-electrical insulator when solid
-electrical conductors whenmolten/dissolved
-brittle
Why do ionic bonds have a very high melting point?
strong electrostatic forces between oppositely charged ions
Why are ionic bonds soluble in h20?
h20 is very polar so can disrupt forces between ions and break them up
Why are ionic bonds brittle?
when moved ions are no longer alternately arranged so they repel each other and the lattice breaks
What is covalent bonding?
- the sharing of outer electrons to achieve a full shell
- with electrostatic attraction between the shared electrons and the positive nucleus.
What types of covalent bonds exist?
Single, double, and triple bonds,
What is a dative covalent (coordinate) bond?
- A bond where one atom donates a pair of electrons to another atom
- For example, ammonia (NH₃) donates a lone pair to H⁺.
- formed when an electron deficient atom accepts a lone pair of electrons from an atom with a lone pair of electrons
How is a dative covalent bond represented?
- With an arrow showing the direction of electron donation
- from the donor to the acceptor
What is the structure of graphite?
- consists of hexagonal layers
- each carbon bonded three times, and the fourth electron delocalized.
Why can graphite conduct electricity?
Delocalized electrons can carry charge, enabling conductivity
Why does graphite have a high melting point?
Strong covalent bonds require a lot of energy to break.
Why is graphite slippery and low density?
Weak intermolecular forces between layers allow them to slide, and the layers are far apart compared to covalent bond lengths.
What is the structure of diamond?
Each carbon atom is bonded four times in a tightly packed lattice.
Why is diamond non-conductive?
no free electrons to charge
What are the similarities between diamond and graphite?
- Both have high melting points due to strong covalent bonds
- both insoluble in water because the bonds are too strong to break.
What are the names and bond angles of molecule with no lone pairs?
What are the names and bond angles of molecules WITH lone pairs?