chapter 8 Flashcards
structure
refers to the way atoms are arranged in space
bonding
the forces that hold adjacent atoms together
chemical bond
a net force that results from the re- arrangement of electrons of atoms during a chemical reaction
covalent bonding
the sharing of electrons from each atoms outermost shell ( valence electrons)
ionic bond
a force of attraction between charged ions
metallic bonding forces
atoms in an extended lattice are immerged in a sea of delocalised electrons
octet of electrons
the valence shell of atoms can accommodate eight electrons
octet rule
many atoms share , gain or loose electrons in order to achieve an octet of valence electrons
bond pair
electrons that are involved in bonding
lone pair
electrons that are not involved in bonding
electronegativity
a measure of the ability of atoms in a molecule to attract valence electrons
what is electronegativity used for
it is used to determine the bonds
give the electronegativity difference values for the different bonds
02 ionic bonds
dative covalent bond
covalent bond where the two electrons involved in the bond come from only one atom
bond length
the distance between the nuclei of atoms that are chemically bonded
bond dissociation enthalpy
energy required to break a bond
- should be equal to the energy released when a bond is formed
how do the number of bond affect the bond length ?
the bond length decreases as the number of bonds increase
what are the two types of reactions?
- endothermic
- exothermic
endothermic reaction
- breaking of bonds \
- enthalpy change is greater than zero
- energy is absorbed
- energy of products is higher than that of reactants
exothermic reaction
- forming of bonds
- enthalpy change is greater than zero
- energy is released
- energy of the products is less than that of reactants
enthalpy change
the difference between the energy of the products and the energy of reactants
bond order
the number of bonding pairs divide by the number of bonding atoms
what does the bond order indicate ?
it indicates the stability of the bonds
- the higher it is the stronger the bond
