Structure And Bonding Flashcards
What is the melting and boiling points of ionic compounds?
High
Giant ionic lattice held together by strong electrostatic forces
Are ionic compounds soluble?
Tend to be
Water molecules are polar
Water molecules are attracted to charged ions
Do ionic compounds conduct electricity?
When molten or dissolved
Ions carry a charge
What is the formula of the following ions Nitrate Carbonate Sulfate Ammonium
NO3 -
CO3 -2
SO4 -2
NH4 +
What is a covalent bond?
Strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms
What is a dative covalent bond?
Both electrons come from one atom
What is bond enthalpy?
Measures energy required to break a covalent bond
Which electron pairs repeal the most?
Lone pair/ lone pair then lone pair/ binding pair then bonding pair
What shape has 2 electron pairs around the centre and what is the bond angle?
Linear molecule
180
CO2
What molecule has a bond angle of 120?
Triage all planer
3 pairs no lone
BF3
What are the different molecule shapes with 4 electron pairs?
Tetrahedral - no lone 109.5 CH4
Trigonal pyramidal - 1 lone 107 NH3
Nonlinear - 2 lone 104.5 H2O
What shape is a molecule with 6 electron pairs?
Octahedral - 90
SF6
What is electronegativity?
An atoms ability to attract the electron pair in a covalent bond
How can covalent bonds be polarised by differences in electronegativity?
Electrons are pulled towards the most electronegative atom making a polar bond
Cause a permanent dipole
When is a molecule polar?
If it’s not symmetrical - charges don’t cancel