TOPIC C2 - BONDING, STRUCTURE AND PROPERTIES OF MATTER Flashcards
When are ions made?
when electrons are transferred
What are atoms trying to form when they lose or gain electrons to form ions?
achieve a full outer shell/stable electronic structure like a noble gas
Atoms with full outer shells are stable
what group are noble gases on the periodic table?
group 0
what happens when metals form ions?
they lose electrons from their outer shell to form positive ions
what happens when non-metals form ions?
they gain electrons into their outer shell to form negative ions
what are the electrons lost or gained the same as?
the charge on the ion
eg if 2 electrons are lost the charge is 2+
if 3 electrons are gained charge is 3-
what groups are most likely to form ions?
1, 2, 6, 7
what are group 1 and 2 elements?
do they lose or gain electrons?
metals
lose electrons to form positive ions
what are group 6 and 7 elements?
do they lose or gain electrons?
non-metals
gain electrons to form negative ions
why do simple ions often have noble gas electronic structure?
noble gas electronic structures have a full outer shell which is a stable structure
what charge do group 1 elements form?
1+ ions
what charge do group 2 elements form?
2+ ions
what charge do group 6 elements form?
2- ions
what charge do group 7 elements form?
1- ions
What is ionic bonding?
transfer of electrons when a non-metal and a metal react together
how does ionic bonding work?
metal atom loses electrons to form positively charged ion, non-metal gains these electrons to form negatively charged ions. Oppositely charged ions are strongly attracted to each other by electrostatic forces - this attraction is called an ionic bond.
What structure do ionic compounds have?
structure called giant ionic lattice
ions form closely packed regular lattice, there are very strong electrostatic forces of attraction between oppositely charged ions in all directions in the lattice.
what is sodium chloride made up of?
sodium ions (cations - an ion with a positive charge) chloride ions (anions - an ion with negative charge)
Which ions are larger in size and occupy the corner and centred positions in sodium chloride?
chloride ions
which ions are smaller in size and occupy the octahedral voids in sodium chloride?
sodium ions
list all properties of ionic compounds
high melting + boiling points due to many strong bonds between the ions, requires lots of energy to overcome this attraction
when solid, ions held in place so compound cannot conduct electricity, however when they melt ions are free to move and they’ll carry electric charge
some ionic compounds dissolve in water, ions separate and are free to move in solution so they’ll carry electric charge.
