chem bonding and structure

Question 1

structure of ionic compound

Answer 1

giant ionic lattice structure

Question 2

structure of molecules

Answer 2

simple molecular structure

Question 3

structure of macromolecules

Answer 3

giant molecular structure

Question 4

structure of metals

Answer 4

giant metallic structure

Question 5

bonding within ionic compound

Answer 5

strong electrostatic forces of attraction between cations and anions

Question 6

bonding within molecules

Answer 6

1) strong covalent bonds between atoms
2) weak intermolecular forces of attraction between molecules (VDW)

Question 7

bonding within macromolecules

Answer 7

strong covalent bonds between atoms

Question 8

bonding within metals

Answer 8

strong electrostatic forces of attraction between metal cations and delocalised electrons

Question 9

electrical conductivity of ionic compounds

Answer 9

good in molten or aq states,

in solid states, strong EFOA between oppositely charged ions hold the ions in fixed position. The ions can only vibrate about their fixed position and are not able to move about freely. hence there are no mobile charge carriers to conduct electricity.

in molten or aq states, strong EFOA between oppositely charged ions are overcome. these ions are free to move around. hence electricity can be conducted by these mobile ions

Question 10

electrical conductivity of molecules

Answer 10

poor

they are neutral molecules and do not contain mobile ions or delocalised electrons to act as charge carriers to conduct electricity

except for those that dissociate to form ions (basically acids)

Question 11

electrictal conductivity of macromolecules

Answer 11

does not conduct electricity except graphite

all the outer shell electrons of carbon atoms are used to form covalent bonds hence there are no delocalised electrons to conduct electricity

but graphite conducts electricity, 1 valence electrons per carbon atom is not used to form covalent bonds. these electrons are delocalised d along the same plane and allow graphite to conduct electricity along the laters

Question 12

mp/ bc of ionic compound

Answer 12

high. ionic compounds have giant lattic structure and strong efoa between oppositely charged ions. larger amount of energy is needed to overcome strong efoa between oppositely charged ions

Question 13

mp/bp of molecules

Answer 13

low, because between molecules, there are only weak intermolecular molecules holding them tgt, only a small amt of energy is needed to overcome this weak intermolecular forces of attraction between molecules.

Question 14

mp / bp of macromolecule

Answer 14

very high (greater than 3000) because large amts of energy is needed to overcome the numerous strong covalent bonds between atoms inn giant structure

Question 15

mp / bp of metals

Answer 15

high. metals have a giant metallic structure with strong efoa between cations and sea of delocalised electrons. a large amount of energy is required to overcome these strong efoa between cations and sea of delocalised electrons

Question 16

physical state of ionic compound at rtp

Answer 16

solid

Question 17

physical state of molecules at rtp

Answer 17

liquid / gas

Question 18

physical state of macromolecules at rtp

Answer 18

solid

Question 19

physical state of metals at rtp

Answer 19

solid, except for mercury

Question 20

how are metallic bonds formed

Answer 20

metals have low ionisation energies, and lose electrons easily to become ions. their valence electrons form a sea of delocalised electrons. hence, efoa between sea of delocalised electrons and metal cations are formed.

Question 21

how are ionic bonds formed

Answer 21

electrons are transferred from metal atoms to non metal atoms, forming cations and anions with stable electronic configuration of noble gas. they are held together in giant ionic lattice by strong efoa because of oppositely charged ions