bonding

Question 1

what factors affect metallic bond strength

Answer 1

charge density of cation and number of delocalised e-

Question 2

how does charge density of cation and number of delocalised e- affect metallic bond strength

Answer 2

larger magnitude of charge density —> stronger attraction between cation and delocalised e-

larger number of delocalised e- —> more extensive interactions between cation and delocalised e-

Question 3

what factors affect ionic bond strength

Answer 3

lattice energy

Question 4

how does lattice E affect ionic bonds

Answer 4

magnitude of LE - modules q+ x q- divided by the radius of the two ions

Question 5

what factors affect covalent bond strength

Answer 5

1.bond length
2.multiplicity of bond
3.polarity of bond
4.proximity of lp

Question 6

how do bond length, multiplicity of bond, polarity of bond and proximity of lp affect bond strength

Answer 6

bond length - bigger size of atoms = more diffuse orbitals and less effective overlap of orbitals so weaker bond

multiplicy - greater no. of shared e- pairs means stronger electrostatic FOA between shared e- and nucleus

polarity - increased bond strength due to additional electrostatic FOA between partial charges

proximity - close proximity results in excessive repulsion that weakens C bond

Question 7

how do bond length, multiplicity of bond, polarity of bond and proximity of lp affect bond strength

Answer 7

bond length - bigger size of atoms = more diffuse orbitals and less effective overlap of orbitals so weaker bond

multiplicy - greater no. of shared e- pairs means stronger electrostatic FOA between shared e- and nucleus

polarity - increased bond strength due to additional electrostatic FOA between partial charges

proximity - close proximity results in excessive repulsion that weakens C bond

Question 8

why do ionic bonds have some covalent character

Answer 8

cation attracts outer e- of anion, polarizing the anions electron cloud. polarization pulls e- cloud into region between the nuclei resulting in partial sharing of e-

Question 9

what is the degree of C character dependent on

Answer 9

polarizing power of cation which is dependent on charge density
size of anion - bigger means more polarisable

Question 10

why do covalent bonds have ionic character

Answer 10

two diff electronegativities means shared pair of e- pulled closer to the more electronegative atom and it aquires a partial negative charge while the other attain partial positive charge

Question 11

ionic character of C bonds dependent on what

Answer 11

dependent on dipole moment

Question 12

list shape and bond angle for diff number of lp and bp

Answer 12

2 0 linear 180
3 0 trigonal planar 120
2 1 bent 117.5
4 0 tetrahedral 109.5
3 1 trigonal pyramidal 107
2 2 bent 104.5
5 0 trigonal bypyramidal 120 and 90
4 1 see-saw
3 2 T-shaped
2 3 linear 180
6 0 octahedral 90
5 1 square pyramidal
4 2 square planar

Question 13

factors affecting id-id interactions

Answer 13

no. of electrons/e- cloud size - greater no. of e- the greater the ease of e- cloud polarization, the stronger the id-id

greater SA for molecular interaction means stronger id-id interactions and higher extent of molecular interaction

Question 14

factors affecting pd-pd interactions

Answer 14

dipole moment - larger means more strong pd-pd interactions

Question 15

factors affecting H bonds

Answer 15

extent of H bonds which is dependent on the number of H covalently bonded to highly electronegative atom and the number of lp on highly electronegative atom

larger dipole moment of HX bond means stronger H bonds

Question 16

why does 2-nitrophenol and 4nitro-phenol have diff bp

Answer 16

2-nitrophenol forms intramolecular H bonds meaning fewer sited are available to form intermolecular H bonds so the extent of intermolecular H bonds is lower. since boiling involves overcoming FOA between molecules, it has a lower bp

Question 17

are giant metallic structures soluble

Answer 17

soluble in polar as they form ion-dipole interactions
non-soluble in non-polar as they form ion-induced dipole int

Question 18

are giant molecular structures soluble

Answer 18

no they either form pd-id in polar solvents or id-id w non-polar

Question 19

are simple molecules soluble

Answer 19

only if they are dissolved in solvent of the same type of bonds as them