3.1.3 Bonding

Question 1

What is electronegativity

Answer 1

The ability of an atom to attract the pair of electrons in a covalent bond.

Question 2

What 3 factors do electronegativity depend on

Answer 2

size of positive charge in the nucleus
Atomic radius - the closer the bonding pair to the nucleus
shielding - greater shielding, lower electronegativity

Question 3

What forces of attraction are in ionic bonds

Answer 3

Electrostatic forces of attraction

Question 4

Ionic bond is made form a

Answer 4

Metal and non-metal

Question 5

Why do atoms react

Answer 5

To achieve electron configuration of a Nobel gas
Full outer shell of electrons

Question 6

How are electrons transferred between non-metal and metal in ionic bond + charges

Answer 6

Metal loses electrons to form a positive ion
Non-metals gains electrons to form a negative ion

Question 7

How are the ions arranged in an ionic bond

Answer 7

A giant lattice structure

Question 8

Shapes of molecules
2 bond
3 bond
4 bond
5 bond
6 bond

Answer 8

Linear
Triangular planar
Tetrahedral
Trigonal biprymadial
Octahedral

Question 9

Formula of ammonium

Answer 9

NH4 +

Question 10

Formula of Carbonate ion

Answer 10

CO3 -2

Question 11

Formula hydroxide ion

Answer 11

OH-

Question 12

Formula nitrate ion

Answer 12

NO3 -

Question 13

Formula sulphate ion

Answer 13

SO4 -2

Question 14

Ionic compounds - electrical conductivity

Answer 14

Only when molten or dissolved not solid
The ions are held in place by electrostatic forces of attraction and are not free to move and carry charge

Question 15

Ionic compound - Melting point

Answer 15

High melting point
The giant ionic lattices are held together by strong electrostatic forces of attraction which act in all directions

Question 16

Ionic compounds - solubility

Answer 16

Tend to be soluable in water.
Water molecules are polar overcomes electron static forces of attraction
Pulls ions away from lattice and dissolves them

Question 17

Angles in linear molecule

Answer 17

180

Question 18

Angle in Trigonal planar

Answer 18

120

Question 19

Angles in Tetrahedral

Answer 19

109.5

Question 20

Angles in Trigonal biprymidial

Answer 20

90
120

Question 21

Angles in octahedral

Answer 21

90

Question 22

In a covalent bond electrons are….

Answer 22

Shared

Question 23

In simple covalent molecules what determines the property of the molecule

Answer 23

Intermolecular forces

Question 24

What is expansion of the octet rule

Answer 24

Usually period 3
Can have more than 8 electrons on outer shell

Question 25

why do simple covalent compounds have low melting and boiling points

Answer 25

Low strong covalent bonds between atoms in a molecule weak intermolecular forces of attraction between molecules which determine their properties

Question 26

giant covalent is also known as

Answer 26

macromolecular

Question 27

graphite structure

Answer 27

sheets of flat hexagons 3 bonds to each carbon delocalised electrons between layer

Question 28

properties of graphite

Answer 28

lubricant- weak bonds between layers mean they can slide over each other conductive - delocalised electrons are free to move and carry a charge. low density- layers are far apart can be used in sports equipment

Question 29

structure diamond

Answer 29

carbon bonded to 4 other carbons crystal lattice structure

Question 30

properties diamond

Answer 30

cant conduct electricity- no free electrons to move and carry a charge high melting point- strong covalent bonds, lots of energy to overcome good thermal conductor - vibrations easily travel through the stiff lattice

Question 31

give an example of each type of molecule Ionic Metallic Simple molecular Macromolecular x2

Answer 31

ionic - sodium chloride metallic - magnesium simple molecular-iodine macromolecular - diamond, graphite

Question 32

Positive ions are sometimes called

Answer 32

cations.

Question 33

Negative ions are sometimes called

Answer 33

anion

Question 34

what is a dative covalent bond?

Answer 34

where one atom provides both electrons in shared pair

Question 35

how is a dative covalent bond shown on a diagram (From which atom to which)

Answer 35

the arrow points away from the atom that has provided the electrons

Question 36

what 2 conditions must there be for a dative covalent bond to occur

Answer 36

1 atom has a lone pair of electrons the other doesn't have any electrons to share

Question 37

a dative covalent bond is same or different to a 'normal' covalent bond

Answer 37

same

Question 38

what is metallic bonding + bonding?

Answer 38

a lattice of positively charged ions surrounded by a ‘sea’ of delocalised electrons. This produces a very strong electrostatic force of attraction between these oppositely charged particles.

Question 39

which have greater repulsion loan pairs or bonding pairs

Answer 39

loan pairs

Question 40

how much do loan pairs reduce a bonding angle

Answer 40

2.5 degrees

Question 41

does a loan pair becoming a dative covalent bond have any effect on the angle degree

Answer 41

no the angles would act the exact same as if they were all covalent bonds

Question 42

electron negativity increases as you move ( in general)

Answer 42

to the top-right of the periodic table (excluding nobel gases)

Question 43

opposite charges on a polar molecule can only cancel if

Answer 43

they are opposite e.g. linear molecule or equal charges act in all directions

Question 44

3 types of intermolecular forces

Answer 44

Van Der Waals forces permanent dipole-dipole interations hydrogen bonds

Question 45

Van Der Waals strength

Answer 45

weak and easily broken

Question 46

How do van der waals occur

Answer 46

Random movement of electrons in one molecule creates a dipole Induces a dipole in a neighbouring molecule These temporary dipoles attract

Question 47

the strength of van der Waals depends on the

Answer 47

number of electrons

Question 48

which molecules can experience permanent dipole-dipole forces

Answer 48

only molecules with a permanent dipole e.g. water

Question 49

the strength of a permanent dipole-dipole interaction decreases as

Answer 49

the electronegativity decreases

Question 50

which is the strongest intermolecular force

Answer 50

hydrogen bonds

Question 51

what are the two conditions for hydrogen bonding

Answer 51

hydrogen atom bonded to a strongly electronegative element the electronegative atom must have at least 1 pair of electrons

Question 52

which 3 elements for hydrogen bonds

Answer 52

oxygen, fluorine, nitrogen

Question 53

why is ice less dense than water

Answer 53

molecules arranged in an ordered structure stabilised by a network of hydrogen bonds molecules are further apart than in liquid so ice is less dense

Question 54

suggest why the electronegativity of the elements increases from lithium to fluorine

Answer 54

increased number of protons same shielding

Question 55

2 bonding pairs name

Answer 55

Linear

Question 56

2 bonding 1 lone

Answer 56

Bent / v-shaped

Question 57

3 bonding pairs

Answer 57

Trigonal planar

Question 58

4 bonding pairs

Answer 58

Tetrahedral

Question 59

3 bond 1 loan

Answer 59

Trigonal pyramidal

Question 60

5 bond

Answer 60

Trigonal biprymidal

Question 61

4 bond 1 loan

Answer 61

See saw

Question 62

3 bond 2 loan

Answer 62

T-shape

Question 63

6 bond

Answer 63

Octahedral

Question 64

5 bond 1 loan

Answer 64

Square pryramid

Question 65

4 bond 2 loan

Answer 65

Square planar

Question 66

Explain how a permanent dipole-dipole forces arise between hydrogen and chlorine molecules

Answer 66

Large difference in electronegativity leads to bond polarity The chlorine has a § - charge and the hydrogen has a §+ charge THERE IS AN ATTRACTION BETWEEN THE §+ AND §- CHARGES § - means slight

Question 67

Which type of structure has the intermolecular forces hydrogen bonding dipole-dipole etc

Answer 67

Simple molecular covalent If these are not in the question then talk about ionic, metallic, covalent bonding instead refer to Spring CAT q2) This is very important

Question 68

Metal + water E.g. Sodium + water

Answer 68

Metal hydroxide + hydrogen Na + H20 —> NaOH + 1/2H2 ALWAYS BALANCE

Question 69

Formula phosphate ion

Answer 69

PO4 -3

Question 70

Formula hydrogencarbonate

Answer 70

HCO3 -

Question 71

Ammonia formula

Answer 71

NH3

Question 72

Acid + metal hydroxide =

Answer 72

Salt + water

Question 73

How many loan pairs does oxygen have when drawing hydrogen bonding

Answer 73

2

Question 74

Metal + steam

Answer 74

Metal oxide and hydrogen

Question 75

3 bond 1 loan bond angle

Answer 75

107