bonding Flashcards
what is an ionic bond
the ionic bond is the electrostatic force of attraction between a positively charged metal ion and a negatively charged non-metal ion
what happens in ionic bonding
the metal ion loses an electron and the non mental gain
what is an ionic lattice
a regular arrangement of alternating positive and negative ions
what do the endings -ide and -ate tell you about a substance
-ide is a metal reacting with a non-metal forms an -ide compound
-ate is a metal reacting with a non-metal and oxygen to from an -ate compound
what particles and forces are present in ionic compounds
electrostatic forces of attraction and ions (charged particles)
why do ionic compounds have high melting and boiling points
they have strong electrostatic forces of attraction which are hard to overcome
why do ionic compound only conduct electricity when liquids or dissolved
because their ions are free to move from place to place. ionic compounds cannot conduct electricity when solid, as their ions are held in fixed positions and cannot move
what is a cation
an ion with a positive charge (lost electrons)
what is an anion
an ion with a negative charge (gained electrons)
explain why ionic compounds are usually solid at room temperature
strong electrostatic forces
which require a lot of energy to overcome
how are covalent bonds formed
when pairs of electrons are shared by atoms
why do simple molecular compounds have low melting and boiling points
very little energy is needed to overcome the intermolecular forces
why are simple molecular compounds poor electrical conductors
there are no free ions or electrons to carry the charge
what is a polymer
large molecules made up of repeating chains called monomers
how are simple molecular structures different from giant covalent structures
simple: have weak intermolecular forces so usually gases or liquids at room temp (low melting and boiling points), dont conduct electricity (no charged particles)
giant: no weak intermolecular forces present between molecules as there are no molecules, only covalent bonds, so substances are solid at room temp, they have high melting and boiling points as they have many strong covalent bonds, most cannot conduct electricity as they do not have free electrons nor charged particles
what are allotropes
different forms of the same element with different structures
what are some allotropes of carbon
diamond, graphite
explain the differences in structure between the different allotropes of carbon
diamond- each C atom has 4 covalent bonds
graphite- each C atom has 3 covalent bonds
what are the properties of diamond and graphite
diamond- doesnt conduct electricity as there are no free moving charges. has a high melting point because a large amount of energy is needed to overcome the many strong covalent bonds
graphite- does conduct electricity as there are delocalised electrons that are free to move between layers of graphite. high melting points due to strong covalent bonds
what are the uses of diamond and graphite
diamond- very hard so used for cutting tools and jewellery
graphite- used as a lubricant as the layers can slide over each other
what are fullerenes
molecules of carbon arranged inclosed tubes /hollow balls
how are particles arranged in metals
the metal atoms are arranged in a regular pattern of layers, with delocalised electrons able to move between them
what are the properties of metals in terms of bonding
high melting and boiling points- there are strong electrostatic forces of attraction between the positive metal ions and the negative delocalised electrons which require a lot of energy to break
good conductors of heat and electricity- the delocalised electrons are free to move and carry a charge through the whole structure
malleable- arranged in layers which slide over each other when force is applied~
what does malleable mean
can be bent without breaking
