Chemistry- mr patel

?
What does the shell closest to the nucleus have?
The lowest energy
1 of 107
What are sub shells ?
What each shell is divided into and they all have different amounts of energy
2 of 107
What is an orbital?
What each sub shell is made up of
3 of 107
Define orbital
A 3D region of space which two electrons can occupy
4 of 107
What shape and capacity is an s sub shell?
A sphere shape and can hold two electrons
5 of 107
What shape and capacity is a p sub shell?
A dumbbell shape with three orbitals which hold two electrons in them each (6 in total)
6 of 107
Which sub shells are filled first ?
The lowest energy ones first
7 of 107
What do electrons in the same orbital have?
Opposite spin
8 of 107
Define molecule
2 atoms held together by covalent bonds
9 of 107
What can a molecule be classed as is the atoms are different ?
A compound
10 of 107
Define compound
2 atoms which are chemically bonded and are different
11 of 107
What bonds can compounds form?
Ionic or covalent
12 of 107
Define covalent bond
Strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms
13 of 107
Define ion
Atoms which loose or gain electrons
14 of 107
Define ionic bond
Electrostatic attraction between positive and negative ions
15 of 107
What are dative (co-ordinate) covalent bonds?
When one atom provides both the shared electron
16 of 107
What is the average bond empathy?
Energy required to break the bond
17 of 107
What does the strength of a covalent bond depend on?
How much outer atomic orbitals overlap and how strongly attracted the atomic nuclei are to the shared pair of electrons
18 of 107
Define ionic lattice
A repeating pattern of oppositely charged ions
19 of 107
What are the properties of ionic structures?
Conduct electricity when molten, high melting and boiling points and soluble in polar substances
20 of 107
How do ionic substances conduct electricity?
The charged ions which are free to move carry the charge
21 of 107
Why do ionic substance have a high melting and boiling point ?
The strong electrostatic forces require a lot of energy to overcome
22 of 107
What does the number of pairs of electrons in the outer shell of a molecule determine?
The shape of the molecule
23 of 107
What is a shared pair of electrons called?
A bonding pairs
24 of 107
What is an unshared pair of electrons called?
Lone pairs
25 of 107
What is the electron pair repulsion theory?
The theory that lone pairs of electrons repel more than bonding pairs
26 of 107
What is the shape and angle of a molecule which has two bonding pairs?
Linear= 180
27 of 107
What is the shape and angle of a molecule which has 3 bonding pairs?
Trigonal planar= 120
28 of 107
What is the shape and angle of a molecule which has Two bonding pairs and one lone pair?
Non linear/ bent= less than 120 (117.5)
29 of 107
What is the shape and angle of a molecule which has 4 bonding pairs?
Tetrahedral= 109.5
30 of 107
What is the shape and angle of a molecule which has 3 bonding pairs and 1 lone pair?
Trigonal pyramidal= 107
31 of 107
What is the shape and angle of a molecule which has 2 bonding and 2 lone?
Non linear= 104.5
32 of 107
What is the shape and angle of a molecule which has 5 bonding pairs?
Trigonal bipyramidal=120, 90
33 of 107
What is the shape and angle of a molecule which has Six bonding pairs?
Octahedral = 90
34 of 107
How do u calculate the number of electron pairs?
Find central atom, work out electrons in outer shell, molecular formula tell u how many atoms are bonded, add up electrons, divide by two= number of pairs, compare electron pairs to bonds to find any lone pairs
35 of 107
What does a line mean in the flying wedge notation?
Plane with paper
36 of 107
What does a solid wedge mean in flying wedge notation?
Coming out of Paper at you
37 of 107
What does a dotted wedge mean in flying wedge notation ?
Coming out behind the Paper
38 of 107
Define electro negativity
Ability of an atom to attract the bonding electrons in a covalent bond
39 of 107
What does FONCI stand for?
Most electronegative elements- fluorine, oxygen, nitrogen, chlorine
40 of 107
How does electronegativity change as you go across the periodic table?
Increases
41 of 107
How does electronegativity change as you go down the periodic table?
Increases
42 of 107
Why is there this trend in electronegativity?
Because there are more proteins and less electron shells
43 of 107
What does a difference in electronegativity cause?
Bonds to become polarised and form a dipole
44 of 107
Define dipole
A difference in charge between two atoms
45 of 107
What type of covalent bond do diatomic gases have and why?
Non polar bonds because they have equal electronegativities
46 of 107
What happens in a covalent bond if there are two types of electronegativities?
Bonds are pulled towards a more electronegative atom creating a polar bond
47 of 107
What causes a permanent dipole?
Difference in electronegativity between two atoms
48 of 107
What are dipoles caused by?
Shift in electron density.
49 of 107
What does a greater difference in electronegativity mean?
The bond is more ionic than covalent
50 of 107
What does the difference in electronegativity need to be to be non polar covalent bond?
Less than 0.4
51 of 107
What does the difference in electronegativy need to be to be a polar bond
Between 0.4 - 2.0
52 of 107
What does the difference in electronegativity need to be to be ionic?
More than 2.0
53 of 107
What is an instantaneous dipole?
When electrons move onto one side they cause temporary dipole which isn’t permanent
54 of 107
What is an induced dipole to dipole?
When instantaneous dipoles cause another instantaneous dipole bcasue the exertions on the other dipole repel electrons causing a domino effect
55 of 107
What is a permanent dipole - dipole?
Difference in electronegativity makes polar molecules interact
56 of 107
What elements does hydrogen bonding occur between?
Covalent bonds between fluorine, oxygen and nitrogen
57 of 107
Define hydrogen bonding
Intermolecular force of attraction between two molecules (very strong)
58 of 107
What properties does hydrogen bonding have ?
Soluble in water, higher melting and boiling point
59 of 107
What’s the bonding between simple covalent like?
Strong bonds between molecules but weak intermolecular forces
60 of 107
Do covalent bonds conduct electricity?
No because they’re uncharged
61 of 107
Why are simple molecules melting and boiling points low?
Because the intermolecular forces are weak
62 of 107
What is the main factor which determines boiling point?
The strength of the induced dipole dipole forces (unless molecule has hydrogen bonds)
63 of 107
What two things effect the strength of the bonds?
Polarity= decreases= so does strength, no. Electrons= more = increased strength
64 of 107
What does the period tell you?
How many shells there is
65 of 107
What does the group tell you ?
No. Of electrons in the outer shell
66 of 107
What year and what did doberner do to the periodic table?
1817- grouped similar elements into triads
67 of 107
What year and what did newlands do to the periodic table?
1863- arrange elements in order of increasing mass “law of octaves”
68 of 107
What year and what did Mendeleev do to the periodic table?
1869-atomic mass but left gaps for elements -similar elements in same group, predict properties of undiscovered elements
69 of 107
What year and what did Moseley do to the periodic table?
1914-increasing atomic number and added Nobel gases
70 of 107
Define periodicity
Trends in physical properties and chemical properties across a period
71 of 107
Define first ionisation energy
Energy needed to pull the first electron from a shell
72 of 107
Define second ionisation energy
Energy needed to remove 1 mole of electrons from 1 mole of gaseous atoms
73 of 107
What does a low ionisation energy mean?
It’s easier to pull electron away
74 of 107
What factors effect ionisation energy ?
Nuclear charge, atomic radius and shielding
75 of 107
How does nuclear charge effect ionisation energy?
More protons= more positive= electrons more strongly attracted=higher ionisation energy
76 of 107
How does atomic radius effect ionisation energy?
Larger nucleus= less attraction= less energy
77 of 107
How does shielding effect ionisation energy?
More electrons=more shielding= weaker force of attraction
78 of 107
What three factors happen to decrease first ionisation energy?
Number of shells increases, shielding increases and atomic radius increases
79 of 107
What has a bigger effect than nuclear charge?
Shielding and atomic radius
80 of 107
How does the nuclear radius decrease?
More protons= Positive charge of nucleus increase= electrons pulled closer to nucleus
81 of 107
What is normally the trend down the group with ionisation energy?
It decreases because there’s more electron shells so more shielding so electrons repulsed more
82 of 107
What is normally the trend across a period to do with ionisation energy?
Increases as number of protons increases so nuclear pull increases no of shells same so shielding is constant
83 of 107
Define allotrope
Same element in different forms in the same state
84 of 107
How many covalent bonds does diamond have and what shape is it?
4 covalent bonds and a tetrahedral shape
85 of 107
What are the properties of diamond?
High melting point, extremely hard, can’t conduct electricity, won’t dissolve, terms, conductor
86 of 107
How is diamond a good thermal conductor?
Vibration travel easily through the stiff lattice
87 of 107
How many bonds does graphite have and what shape is it?
Three covalent bonds and 1 delocalised electron with sheets of hexagons
88 of 107
What forces are between the sheets of graphite?
Weak dipole dipole forces
89 of 107
What are the properties of graphite and why?
Conduct electricity because of delocalised electrons, weak forces slippery, low density
90 of 107
What are the uses of graphite?
Electrical conductor, lubricant, strong lightweight conductor
91 of 107
What is graphene?
One layer of graphite, one atom thick
92 of 107
What shape are the atoms joined together in graphene?
A hexagon shape
93 of 107
What are the properties of graphene and why?
Good conductor and strong because of delocalised electrons, transparent and light
94 of 107
What are the uses of graphene?
High speed electronics and air craft, touch screens and smartphones
95 of 107
Define metallic bonding
Electrostatic force of attraction between delocalised electrons and metal cations
96 of 107
What is the structure of metallic bonding?
A lattice of closely packed cations packed in a sea of delocalised electrons
97 of 107
What happens to the boiling point if there’s more delocalised electrons?
Increases due to stronger bonding because smaller radius holds electrons closer to the nuclei
98 of 107
How are metals malleable and ductile?
Because there are no bonds holding specific ions together so they can slide over each other
99 of 107
Why are metals good conductors?
Electrons can pass kinetic energy to each other and electrons can carry a current
100 of 107
Why are metals insoluble?
Because they’re strong
101 of 107
What are the products of a group 2 metal reacting with water?
Metal hydroxide + hydrogen
102 of 107
Why is the solution after a group 2 metal reacts with water strongly alkaline?
Because the metal hydroxide produces OH ions
103 of 107
What do you get when a group 2 element reacts with oxygen?
A solid white oxide
104 of 107
What does a metal oxide and water form?
A strong alkaline because they dissolve forming metal hydroxides
105 of 107
What group 2 element is the exception when dissolving with water?
Magnesium oxide because it reacts slowly and isn’t very soluble
106 of 107
What is a dative covalent bond?
When one atom provides both electrons in a covalent bond
107 of 107

Other cards in this set

Card 2

Front

What are sub shells ?

Back

What each shell is divided into and they all have different amounts of energy

Card 3

Front

What is an orbital?

Back

Preview of the front of card 3

Card 4

Front

Define orbital

Back

Preview of the front of card 4

Card 5

Front

What shape and capacity is an s sub shell?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar All resources:

See all All resources »See all Science resources »