Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry AS Level > Physical 1: Bonding > Flashcards

Physical 1: Bonding Flashcards

1
Q

what is ionic bonding?

A

strong electrostatic forces of attraction between oppositely charged ions held in a lattice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

give an example of an ionically bonded substance

A

NaCl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

how high are ionically bonded substances’ boiling point and melting point?

A

high - takes lots of energy to break strong electrostatic forces of attraction between oppositely charged ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

do ionic compounds conduct electricity?

A

yes, when molten/in solution as the ions are free to move and carry charge
they don’t when solid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is simple molecular covalent bonding?

A

strong covalent bonds between atoms, weak van der waals forces of attraction between molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

are there any lone electrons in simple covalent bonding?

A

no - all involved in bonding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

can simple molecular covalent molecules conduct electricity?

A

no - all electrons used in bonding and aren’t free to move

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

do simple molecular substances have a high/low mpt and bpt?

A

low - weak vdw forces of attraction between molecules that don’t take much energy to overcome (these are overcome rather than covalent bonds)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

describe macromolecular covalent bonding

A

lattice of many atoms held together by strong covalent bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

do substances with macromolecular covalent bonds have high/low mpt and bpts?

A

high, as it takes a lot of energy to overcome many strong covalent bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

do substances with macromolecular covalent bonds conduct electricity?

A

most don’t as all electrons are used in bonding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

describe the structure of diamond

A

3D tetrahedral structure of C atoms, with each C atom bonded to four others

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

describe the structure of graphite

A
  • macromolecular covalent
  • each C atom is bonded to 3 others, so it is in layers
  • weak vdws between layers mean they can slide over each other —- soft and slippery
  • one electron from each carbon is delocalised and can carry charge —- conducts electricity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

describe metallic bonding

A
  • lattice of positive metal ions strongly attracted to a sea of delocalised electrons
  • layers can slide over each other —- malleable
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

do metallic compounds have high/low bpt and mpt?

A

high as strong forces of attraction between positive metal ions and negatively charged sea of delocalised electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

do metallic compounds conduct electricity?

A

yes, as the delocalised electrons can move throughout the metal in carry charge

17
Q

how does the strength of metallic bonds change across the periodic table?

A
  • increases — higher mp and bp
  • higher charge on metal ions
  • more delocalised electrons per ion
  • stronger force of attraction between them
18
Q

define electronegativity

A

the ability of an atom to attract the pair of electrons (the electron density) in a covalent bond

19
Q

what affects electronegativity?

A
  • nuclear charge
  • atomic charge
  • electron shielding
20
Q

what is the most electronegative element?

A

Fluorine (4.0 on Pauling’s scale) – has the largest nuclear charge for its electron shielding – small atomic radius

21
Q

how do you get a nonpolar bond?

A

both bonding elements have the same electronegativities

22
Q

when do you get a polar bond?

A

bonding atoms have a different electronegativities

23
Q

what is the strongest type of intermolecular force ?

A

hydrogen bonding

24
Q

what is the weakest type of intermolecular force?

A

van der waals forces

25
Q

describe van der waal’s forces of attraction

A
  • temporary dipoles are created by the random movement of electrons
  • induces dipole in neighbouring molecule
  • temporary induced dipole-dipole attraction aka vdw forces
26
Q

are van der waals forces stronger in smaller or larger molecules?

A

larger - more electrons

27
Q

describe permanent dipole-dipole attractions

A

some molecules with polar bonds have permanent dipoles — forces of attraction between those dipoles and those of neighbouring molecules

28
Q

what conditions are needed for hydrogen bonding to occur?

A
  • O-H, N-H or F-H bond, lone pair of electrons of O, F, N
  • because O, N, and F are highly electronegative, H nucleus is left exposed
  • strong force of attraction between H nucleus and lone pair of electrons on O, N, F
29
Q

why is ice less dense than liquid water?

A
  • in liquid water, hydrogen bonds constantly break and reform as molecules move about
  • in ice, hydrogen bonds hold the molecules in fixed positions; this makes them slightly further apart than in liquid water
30
Q

what is a dative/co-ordinate covalent bond?

A

formed when an electron deficient atom/ion with a lone pair of electrons (not used in bonding)

31
Q

what does the shape of molecules depend on?

A
  • number of electrons in the valence shell of the central atom
  • number of these electrons which are in bonded or lone pairs
32
Q

what does the electron pair repulsion theory state?

A

the electron pairs will take up positions as far away from each other as possible, to minimise the repulsive forces between them

33
Q

which experience the most repulsion of lone/bonding pair repulsion?

A

lone pair-lone pair is the strongest repulsion
lone pair-bonding pair is the middle repulsion
bonding pair-bonding pair is the weakest repulsion

34
Q

what is the shape, diagram and bond angle in a shape with 2 bonded pairs and 0 lone pairs?

A

linear
180 degrees
o—-o—-o

35
Q

what is the shape, diagram and bond angle in a shape with 3 bonded pairs and 0 lone pairs?

A

trigonal planar

120 degrees

36
Q

what is the shape, diagram and bond angle in a shape with 4 bonded pairs and 0 lone pairs?

A

tetrahedral

109.5 degrees

37
Q

what is the shape, diagram and bond angle in a shape with 5 bonded pairs and 0 lone pairs?

A

trigonal bipyramid

90 degrees and 120 degrees

38
Q

what is the shape, diagram and bond angle in a shape with 6 bonded pairs and 0 lone pairs?

A

octahedral

90 degrees

Chemistry AS Level (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions