Bonding Flashcards
What are the 5 properties of ionic substances?
- high melting point
- brittle
- hard
- solids don’t conduct electricity
- melted/ aqueous conduct electricity
why do ionic substances have a high melting point?
- electrostatic attraction is very strong–> must be overcome to melt, thus large amounts of energy required to melt/boil
why are ionic substances hard?
strong electrostatic attraction keeps ions in place tightly
why are ionic substances brittle?
when a strong force is applied, the ions shift out of place and like charges may line up–> when they line up they repel each other and thus result in breakages in the crystal
why do ionic substances not conduct electricity while they are solid?
charges need to be mobile to conduct electricity, but in an ionic lattice, they are stuck in place, thus can’t conduct electricity
why do ionic substances conduct electricity while they are melted/ aqueous
the charges are free to move in an ionic substance that is melted/ dissolved in water, thus can conduct electricity
Lewis formulas show ____ electrons around the element symbol
valence
anions are drawn with a ___ outer shell and a ____ outside the bracket
full, negative charge
cations are drawn ____ any valence electrons, and a ____ outside the bracket
without, positive charge
high electronegative electrons (non-metals) ____ give up electrons, rather ____ electrons to make a ___ outer shell
do not, share, full
molecules are discrete particles that move independently
true/false
true
atoms also form covalent networks/ lattice that have ___ discrete particles
no
are INTRAmolecular bonds easy or hard to break?
very hard
are INTERmolecular bonds easier or harder to break?
easier
what are INTRAmolecular bonds?
covalent bonds within molecules
join atoms to form a molecule
what are INTERmolecular bonds?
between other covalent molecules
why do covalent molecules have a lower melting point?
INTERmolecular bonds between other molecules are broken, this INTERmolecular force is easier to overcome, thus melts/boils easier
why are covalent molecule substances soft?
easy to overcome INTERmolecular forces
do covalent molecular bonds conduct electricity?
no
do covalent networks have INTERmolecular forces? why?
no, there are no discrete molecules
why do covalent networks have a high melting/boiling point?
strong covalent INTRAmolecular bonds must be broken before melting/boiling, thus higher melting/boiling points are required
are covalent network substances hard and brittle?
yes
do covalent networks conduct electricity?
no
metals bond in an ____ array of _____ ions
orderly, positive
in a metallic bond, electrons are ____ from their atoms and are able to move freely around the lattice structure
referred to as being ______
detached, delocalised
what holds the metallic bond lattice together?
electrostatic attraction between positive cations and negative delocalised electrons
metallic bonds are conductors of electricity
true/ false
true
are metallic bonds malleable and ductile?
are they brittle?
yes
no
