pg 174-176

Question 1

how do covalent bonds stay together

Answer 1

electrons are shared between atoms and the shared electron density holds them together

Question 2

how do ionic bonds stay together

Answer 2

electrons are transferred from one atom to another and the compound is held together by attractions between oppositely charged ions

Question 3

define diatomic molecule

Answer 3

a molecule containing only two atoms

Question 4

what causes a polar bond

Answer 4

electrons shared unequally between atoms

Question 5

define bond length

Answer 5

the distance between the centre of two atoms in a molecule

Question 6

what is the bond length for homonuclear atoms

Answer 6

double the value of the atomic radius

Question 7

define bond dissociation enthalpy

Answer 7

standard enthalpy change where a bond is broken

a measure of bond strength

Question 8

the graph for potential energy and distance between nuclei

Answer 8

starts high lots of energy to have them close then dips below 0 then gradually back up to touching 0 where they are too far for any attraction

Question 9

what means a strong bond on a potential energy/distance between nuclei graph

Answer 9

the deeper the minimum of the curve the stronger the bond