C2 BONDING, STRUCTURE AND THE PROPERTIES OF MATTER
No description yet. This curated deck is ready for daily study.
Card preview (21)
what is ionic bonding?
electrostatic attraction between positive and negative ion
how are ionic compounds held together?
giant lattice regular structure that extends in all directions in a substance
properties of ionic compound?
high melting and boiling point does not conduct electricity when solid (ions in fixed position) conduct when molten or dissolved in water - ions are free to move
how are ionic compounds formed? explain in terms of MgO case
reaction of a metal with a non metal electron transfer occurs - metal gives away its outer shell electron to non-metals. Mg is in group 2 so have two available outer shell electrons. O is in group 6 and can accept 2 electrons on its outer shell electron to get full outer shell confiigurations. mg becomes mg2+ and o becomes o2- (oxide)
covalent bond?
shared pair of electrons between two atoms
structure and properties of simple molecular covalent substances?
does not conduct electricity small molecules weak intermolecular forces low melting and boiling point
how do intermolecular forces change as the mass/size of the molecule increases?
they increase (that causes melting/boiling point to increase as well). more energy is needed to overcome these forces
polymers?
very large molecules with atoms linked by covalent bonds
giant covalent substances?
solid , atoms covalently bonded together in a giant lattice. high melting/boiling points - strong covalent bonds mostly don’t conduct electricity (no delocalised e-) e.gs - diamond, graphite, silicon dioxide
describe and explain the property of diamond (allotropes of carbon) ?
four strong covalent bonds for each carbon atom very hard very high melting point does not conduct electricity
describe and explain the property of graphite(allotropes of carbon) ?
• 3 covalent bonds for each carbon atom • layers of hexagonal rings • high melting point • layers free to slide (weak intermolecular forces between layers; soft) • can be used as lubricant conduct thermal and electricity due to one delocalised electron per each carbon atoms
describe and explain the property of fullerenes(allotropes of carbon) ?
hollow shaped molecule based on hexagonal rings but may have 5-7 carbon rings c60 has a spherical shape , simple molecular structure (buckministerfullerene)
describe and explain the property of nanotubes (allotropes of carbon)
cylindrical fullerene with high length to diameter ratio high intensile strength (strong bonds) conductivity (deloc. electrons)
describe and explain the property of graphene (allotropes of carbon)
a single layer of graphite
metallic bonding?
forces of attraction between delocalised electrons and nuclei of metal ions
alloys?
mixture of metals with other elements usually metals
why are alloys harder then pure metals?
different sizes of atoms distorts the layers so they cant slide over eachother
31
31
what does the amount of energy needed to change state from solid to liquid or liquid to gas?
the strength of the forces between the particles of the substances. the nature of particles involved depends on the type of bonding and the structure of the substance. the stronger the forces between the particles the higher the melting point and boiling point of the substance
a pure substance will melt or boil at
a fixed temperature a mixture will melt over a range of temperatures
3 states of matter?
solid , liquid , gas