Topic 4/14

Question 1

What type of bond does not conduct electricity?

Answer 1

Coordinate covalent

Question 2

What state do ionic compounds conduct electricity?

Answer 2

Liquid

Question 3

How many pi and sigma bonds in a triple bond

Answer 3

2 and 1

Question 4

What is coordinate covalent

Answer 4

Bonding electrons only come from one atom

Question 5

What type of bond isnot soluable in water

Answer 5

Covalent because it is a polar solvent

Question 6

Do ionic compounds have resonance structures

Answer 6

No

Question 7

Bond angle of bent (2 domains and two lone pair of electrons)

Answer 7

104.5

Question 8

Bond angle of tetrahedral

Answer 8

109.5

Question 9

Bond angle of trigonal pyrmidal (3 domains and one lone pair of electrons)

Answer 9

106.7

Question 10

Bond angle of trigonal bipyrmidal (5 domains) and octahedral

Answer 10

90

Question 11

What are allotropes

Answer 11

Different forms of an element in the same state

Question 12

Structure of diamond

Answer 12

Tetrahedral, strong covalent so poor electrical conductor

Question 13

Structure of silicon and silicon dioxide

Answer 13

1) Tetrahedral
2) also tetrahedral but each silicon bonded to 4 oxygens

Question 14

Structure of graphite

Answer 14

Sheets of hexagonal rings and each sheet held together by LDF so they can slide

Each carbon atom has one delocalized electron so conduct electricity

Question 15

Graphene

Answer 15

Single layers of graphite, trigonal planar, high strength and good electrical conductor and very reactive

Question 16

Fullerene C60

Answer 16

20 6 carbon rings and 12 5 carbon rings. Delocalized electron but cannot jump from fullerene to fullerne

Question 17

What is the dipole in polar and non polar

Answer 17

Polar have net dipole
Non polar dipoles cancel each other out

Question 18

What is an alloy and name two examples

Answer 18

Two metals or non metal ike carbon mixed in molten. Brass and stainless steal

Question 19

Formal charge

Answer 19

Charge an atom would have if all atoms in the molecule had the same electronegativity

FC = V - (1/2B + NB)

Calculate FC for each molecule, most perferred has negative number over most electronegative element

Question 20

Bond angle of square pyridmidal 5 bonding domains and one lone pair

Answer 20

less than 90

Question 21

Where are delocalized electrons present? Why do they give greater stablotu

Answer 21

In covalent bonds with resonance structures. Charge is spread out so less attractive to pos nucleus

Question 22

What is the wavelength needed to dissociate oxygen and ozone?

Answer 22

Divide bond enthalpy of oxygen or ozone by avrogadros constnat (energy to break one bond)
Find lambda (wavelength) and convert to nanometers (lambda = (hc)/E
Convert o nanometers

Question 23

What is sp3, sp2 and sp hybdridization

Answer 23

no multiple bonds, 1 double bond, 2 double or 1 triple bond

Question 24

Which molecules would form a coordinate covalent bond?

Answer 24

One has to have a lone pair of electrons and other at least one lone pair

Question 25

Bond molecular geometry and angle in ozone

Answer 25

Bent and 116

Question 26

Nitrogen monoxide catalyses décomposition of ozone

Answer 26

RNO + O3 = RNO2 + O2
RNO2 + O3 = RNO + 2O2

Question 27

Define resonance structure

Answer 27

More than one possible positon for pi bond

Question 28

Are ionic or covalent structures higher melting

Answer 28

ionic bc covalent weak imf

bonds BETWEEN compounds are imf whereas covalent bonds IN compounds

Question 29

Describe metallic bonding and how it contributes to electrical conductivity (3)

Answer 29

Electrostatic attraction between lattice of cations and sea of delocalized electrons, mobile electrons responsible for conductivity

Question 30

Molecular geometry of see saw

Answer 30

4 domains and 1 lone pair of electrons

Question 31

What is preferred for formal charge?

Answer 31

Formal charges closest to zero on each atom

Question 32

Why is aluminum malleable?

Answer 32

Layers of cations slide over each other when metal is malleable without breaking bonds because of delocalized electrons.