Bonding, Structure And Properties Of Matter Flashcards
what are ions?
charged particles made when electrons are transferred
talk to me about group 1 metals for ions
lose electrons (1+ charge)
talk to me about group 2 metals for ions
lose electrons (2+ charge)
talk to me about group 6 non-metals for ions
gain electrons (2- charge)
talk to me about group 7 non-metals for ions
gain electron (1- charge)
what is ionic bonding?
the electrostatic attraction between between oppositely charge ions. Ionic bonding occurs between positive metal ions and negative non-metal ion.
what do dot-cross diagrams not show?
compound structure, or the size and arrangement of ions
what are 3 properties of ionic compounds?
1: giant ionic lattice structure - electrostatic forces of attraction between oppositely charged ions act in all directions
2: high melting and boiling points - lots of energy needed to overcome the many strong bonds
3: conduct electricity only when molten or dissolved - ions free to more and carry electric charge
what is a covalent bond?
a shared pair od electrons between two non-metal atoms. Covalent bonding happens in non-metal compounds and in non-metal elements
what do molecular formulae show?
how may atoms of each element are in a compound
what do dot and cross diagrams not show?
relative sizes of atoms or their arrangement in space
what do ball and stick diagrams not show?
which atoms the electrons in the bonds come from
what does the displayed formula not show?
the 3d structure
which compunds do you need to know?
Hydrogen chloride
Water
Ammonia
Methane
which elements do you need to know?
hydrogen
oxygen
nitrogen
chlorine
what are 2 properties of simple molecular substances?
1: low melting and boiling points - mostly gases or liquids at room temperature
2: don’t conduct electricity - there are no charged particles to carry charge
what are polymers?
very long chains of repeating units.
they’re usually solids at room temperature because they have relatively strong intermolecular forces (covalent)
what is a giant covalent structure?
a solid containing atoms which are all bonded to each other by strong covalent bonds
what are 2 properties of giant covalent structures?
1: high melting and boiling points - lots of energy needed to overcome strong covalent bonds
2: don’t conduct relectricity (with a couple of exceptions) - no charged particles to carry charge
talk to me about diamond allotrope.
C atoms form 4 covalent bonds
very hard (property)
high melting point
doesn’t conduct electricity
talk to me about graphite allotrope.
C atoms form 3 covalent bonds. No covalent bonds between layers
soft, slippery (property)
high melting point
conducts electricity and thermal energy
talk to me about graphene.
C atoms form 3 covalent bonds
strong, light (property)
high melting point
conducts electricity (delocalised electron)
what are fullerenes?
they have hollow shapes (eg, buckminsterfullerene, which is spherical and was first to be discovered)
what are nanotubes?
cylindrical fullerenes used in nanotechnology, electronics and materials. They have high length to diameter ratios
