BONDING Flashcards
define ionic bonding?
strong electrostatic forces of attaction between oppositely charged ions. occurs in ionic compounds
ionic compounds like sodium chloride form what structure?
giant ionic lattic structure. -regular strucure, - cubic shape, - giant repeating pattern.
most ionic compounds dissolve in water because water is _____, and hence can do what to break up the structure.
can dissolve in water molescules as water molcules are polar, hence they can attract the + and - ions and hence break up the structure
properties of ionic compounds?
soluble, can conduct electricity when molten or dissolved in solution, as the ions are free to move around,
have high mp as there are many strong electrostatic forces of attraction betweeen oppositely charged ions hence losts of energy is needed to overcome these forces.
define covalent bonding
bonding formed involving the sharing of outer electrons in order for atoms to obtain a full shell, via an (electrostatic force of attraction between the shared pair of electrons and the positive nucleus)
define dative/coordinate bonds, and show the eg of nitrogen with h+ in ammonium
these are where one atom donates 2 electrons to an atom or ion to form a bond. https://merchanttaylorsschools-my.sharepoint.com/:w:/g/personal/tofoma_merchanttaylors_com/EaLW1_e-_tpAh0JJG2KPOCMBXQAwnXTaIGigNW-pWhuatA?e=8TeTHl
eg of giant covalent structures,
graphite and diamond, sio2
compare the properties of diamond and graphite
https://merchanttaylorsschools-my.sharepoint.com/:w:/g/personal/tofoma_merchanttaylors_com/EQ-oXevp7L1Dl1D9SlncNewBMDO3HTSmN-XOXpfzy3wkig?e=CdRqmN
why do molecules have a specific shape with specific angles.
because bonds repel each other equally. both contain electrons so they will want to be as far apart as possible.
lonepair-bondpair relel more than bondpair-bondpair. 2 lone pairs together do what even more then
repel even further
what do lone pairs do
they shange the shape and bond angles by pishing bond pairs closer together. for every lone poair u reduce the bong angles by 2.5 degrees. (some molecules u dont reduce by 2.)
give the name of shapes of molecules with 0 lone pairs, and the bond angles of em
https://merchanttaylorsschools-my.sharepoint.com/:w:/g/personal/tofoma_merchanttaylors_com/EeLDUbeCoCxIiCwp9wXksaUBmhe8vi1IaMBRK9ZNgP-tXw?e=6NMngu
give the name of shapes of molecules with lone pairs, and the bond angles of emj
https://merchanttaylorsschools-my.sharepoint.com/:w:/g/personal/tofoma_merchanttaylors_com/EbDNmMAm05FHgLg8jTMMDPABLOA2dqTaRI6-TGVOLLbaeg?e=oJ9rap
define electronegativity
the ability of an atom to attract a shared pair of electrons (towards itself) in a covalent bond
whats the trent of electrognegativity in the periodic table
the further up and right u go, the more electronegative the element is. (flurorine is the most EN)
the bigger the difference in the EN, the most ____ the bond will be
polar
are hydrocarbons classed as polar or non-polar
non-polar
atoms bonded with the same or similar EN value are not ____
not polar. as the shared electrons sit in the middle
if polar bonds are arranged symmetrically, what effect does that have on the overall polarity.
then u have no overall polarity. (eg, c02
uneven distribution of charge leads to what
polar molecules eg (h2o)
define van der waals and give a diagram
a temporary induce dipole-dipole that only exists when 2 moelcules or atoms are near by. when they move away the dipole interaction is destroyed. the delta+ on one atom or molecule will be attracted to the delta - on aother and a force of attraction is created. (its the weakest IMF)
https://merchanttaylorsschools-my.sharepoint.com/:w:/g/personal/tofoma_merchanttaylors_com/ERzRkXfudYtClZlxncYGq8oBRSnT81NKz2xuJv57YAE8QQ?e=2Ou8bE
VDW forces can hold some molecules in what type of structure?
crystal structure. eg iodine.
HOW DOES THE STRENGTH OF COVALENT BONDS AND VDW FORCES DIFFER IN FOR EG IODINE.
WEAK VDW FORCES HOLDS THE I2 MOLECULES TOGETHER (simple molecular (simple covalent))
sTRONG COVALENT BONDS HOLDS THE 2 IODINE ATOMS TOGETHER.
the bigger the molecule or atom, the more ____
the bigger the molecule or atom, the more VDW forces as u have larger electron clouds
