Brainscape's Knowledge GenomeTM

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


See full index

A-level chemistry unit 1 > unit 1 section 3 bonding > Flashcards

unit 1 section 3 bonding Flashcards

1
Q

what is an ionic bond

A

it is a bond between two oppositely charge ions. held by electrostatic forces of attraction. this is normally a bond between a metal and a non metal

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

what is the ionic formula for ammonium

A

NH^4

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

what is the formula for ammonia

A

NH^3

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

what is the ionic formula for carbonate

A

CO^2-, 3

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

what is the ionic formula for an hydroxide

A

OH-

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

what is the ionic formula for a nitrate

A

NO^- , 3

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

what is the ionic formula for sulfate

A

SO^2- , 4

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

what does electrostatic forces do and are they strong

A

they hold positive and negatively charged ions together. they are strong bonds

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

what is a cation

A

a positive ion

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

what is an anion

A

it is a negative ion

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

what is a lattice

A

it is a regular structure

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

why are giant lattices giant

A

they are giant because they are made up of the same repeating unit

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

give an example of a giant lattice

A

MgO , NaCl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the electrical conductivity behavior of ionic compounds

A

they conduct electricity when they are molten or dissolved but not when they are solid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the melting point of ionic compounds

A

they have high melting points, this is because they are held together by strong electrostatic forces of attraction.

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

what is the behavior of solubility in ionic compounds

A

tend to dissolve in water. water bonds are polar and they pull ions away from the lattice causing it dissolve.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is a simple covalent compound

A

it is a compound that is made up of lots of individual molecules.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what force holds atom in a molecule

A

covalent bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what bond holds molecules within a simple covalent compound

A

weak intermolecular forces of attraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

how are the carbon atoms in graphite arranged

A

the carbon atoms are arranged in sheets of hexagons that are covalently bonded to each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

how are the sheets of flat hexagons in graphite boned between layers

A

the fourth outer electron on each carbon is delocalised and the sheets are bonded by weak van der waals forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are the properties of graphite

A
  • weak bonds in graphite layer is easily broken, allows layers to slide over each other
  • delocalised electron can move freely, therefore graphite can carry a charge/ a current can flow.
  • high melting points due to strong covalent bonds
  • insoluble in any solvent
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what are the properties of diamond

A
  • high melting point
  • extremely hard
  • good thermal conductor, vibrations travel through it easily
  • cannot conduct electricity
  • cannot dissolve in any solvent
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is a co-ordinate / dative bond

A

it is when the bonding electrons comes from one atom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what are lone pairs of electrons

A

electrons that are unshared / not bonded

26
Q

what is a charge cloud

A

it is an area in which an electron can exist.

27
Q

what repels more, lone pair charge clouds or bonding pairs

A

lone pairs

28
Q

what is the valence shell electron repulsion theory

A

it is the theory that lone pair electrons repel more than bonding pair electrons, this causes the bond angles to reduce as the lone pair repels the bonding pairs closer to each other

29
Q

how do you work out the number of electron pairs and bonding pairs and lone pairs

A

central atom group + bonds +charge / 2

  • compare to how many bonds you have to the number you get bonding pairs to lone pairs
30
Q

what is the shape and bond angle of a central atom with two bonding pairs

A

linear , 180

31
Q

what is the shape and bond angle of central atom with three bonding pairs

A

trigonal planar , 120

32
Q

what is the shape and bonding angle of a central atom with two bonding pairs of electrons and one lone pair of electrons

A

bent , 117.5

33
Q

how much does 1 lone pair reduce the bond angle by

A

2.5 degrees

34
Q

what is the shape and bond angle of a central atom with four electron pairs

A

tetrahedral , 109.5

35
Q

what is the shape and bond size of a central atom with 3 bonding pairs and one lone pair

A

trigonal pyramidal , 107

36
Q

what is the shape and bond angle of a central atom with 2 boning pairs and 2 lone pairs

A

bent , 104.5

37
Q

what is the shape and bond angle of a central atom with 5 bonding pairs

A

trigonal bipyramidal , 120 & 90

38
Q

what is the shape and bond angle of a central atom with 4 bonding pairs and 1 lone pair

A

seesaw , 86.5

39
Q

what is the shape and bond angle of a central atom with 6 bonding pairs

A

octahedral , 90

40
Q

what is the shape and bond angle of a central atom with 4 bonding pairs and 2 lone pairs

A

square planar , 90

41
Q

what is electronegativity

A

it is the ability to attract the bonding pair of electrons in a covalent bond.

42
Q

what is electronegativity measured in

A

it is measured in the Pauling scale

43
Q

what is the most electronegative element

A

fluorine

44
Q

are diatomic gases bond polar

A

they are not polar as they have the same electronegativity. the electrons are equally attracted to the both nuclei

45
Q

what is a polar bond

A

it is a bond between two atoms that have different electronegativities. the atoms with the higher electronegativity pulls the electrons closer to that atom, this makes the bond polar as the electrons are not spread out evenly.

46
Q

what is a dipole

A

a dipole is a difference in charge between two atoms caused by a shift in electron density in the bond

47
Q

what is a polar molecule

A

it is a molecule that has a permanent dipole because the charge is unevenly distributed

48
Q

how do you know if a molecule has an overall permanent dipole

A

whether the molecule has a permanent dipole depends on the shape of the molecule, it depends on whether the bonds are arranged symmetrically and the dipoles cancel each other out.

49
Q

what are intermolecular forces

A

they are forces between molecules. they are weaker than covalent bonds

50
Q

what are the three types of intermolecular forces of attraction

A

hydrogen bonding, permanent dipole-dipole , van der waals ( induced dipole-dipole)

51
Q

explain how an induced dipole-dipole bond works

A

electrons in a charge cloud move really fast and at any particular moment in time the electrons can be found more to one side than the other, this causes a temporary dipole in the atom. this dipole can cause another dipole in the other direction in a neighboring atom. the two dipoles are attracted to each other, the second dipole can cause another dipole in a third atom.

52
Q

why do larger molecules have stronger van der waals

A

they have stronger van der waals because they have larger charge clouds which means they have stronger van der waals.

53
Q

what is permanent dipole forces

A

this is forces between molecules that have permanent dipoles. the weak electrostatic forces between the δ+ and the δ- charges on the neighboring molecules causes the permanent dipole

54
Q

what is the difference between induced dipole-dipole and a permanent dipole force

A

induced dipole is between atoms and the permanent dipole is between molecules.

55
Q

what is the strongest intermolecular force

A

hydrogen bonding

56
Q

what is hydrogen bonding

A

it is a bond between hydrogen and either nitrogen, fluorine and oxygen. these 3 elements are very electonegative so they draw bonding electrons away from the hydrogen atom.

57
Q

what affect does hydrogen bonding have on the properties on substances

A

have higher boiling and melting point due to the amount of energy needed to overcome the hydrogen bond.

58
Q

explain why melting point of metallic bonded molecules is high

A

they have high melting points due to the strong electrostatic forces of attraction between the positively charged metals ions and the negatively charged sea of delocalised electrons. the number of electrons per atom affects the melting point, the more the stronger the bonding and the higher the melting point will be

59
Q

why are metals easy shaped

A

they can be easily shaped as there are no specific bonds holding ions together, so therefore they can slide over each other.

60
Q

are metals soluble

A

they are insoluble except in liquid metals due to the strength of the metallic bonds.

A-level chemistry unit 1 (6 decks)

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