Chemistry paper 1 Flashcards
(135 cards)
1
Q
Atomic structure (keywords) - Atom
A
The smallest part of an element that can still be recognised as that element.
2
Q
Atomic structure (keywords) - Atomic number
A
The number of protons (which equals the number of electrons) in an atom. It is sometimes called the proton number.
3
Q
Atomic structure (keywords) - Electron
A
A tiny particle with a negative charge. Electrons orbit the nucleus of atoms or ions in shells.
4
Q
Atomic structure (keywords) - Isotope
A
Atoms that have the same number of protons but different number of neutrons.
5
Q
Atomic structure (keywords) - Mass number
A
Mass number the number of protons plus neutrons in the nucleus of an atom.
6
Q
Atomic structure (keywords) - Proton
A
A tiny positive particle found inside the nucleus of an atom.
7
Q
Atomic structure (keywords) - Nucleus (of an atom)
A
The very small and dense central part of an atom that contains protons and neutrons.
8
Q
Atomic structure (keywords) - Product
A
A substance made as a result of a chemical reaction.
9
Q
Atomic structure (keywords) - Reactant
A
A substance we start with before a chemical reaction takes place.
10
Q
Atomic structure (keywords) - Law of conservation of mass
A
The total mass of the products formed in a reaction is equal to the total mass of the reactants.
11
Q
Key parts for periodic table -
Group 1
A
Alkali metal
Reactive metals
Always forms +1 ions
12
Q
Key parts for periodic table -
Group 2
A
Alkali earth metals
Less reactive
Always form +2 ions
13
Q
Key parts for periodic table -
Transition metals
A
Typical metals
Shiny, malleable & high melting points
14
Q
Key parts for periodic table -
Group 7
A
Halogens
Reactive gases
Always form -1 ions
15
Q
Key parts for periodic table -
Group 0
A
Noble gases
Unreactive
Full outer shells
16
Q
Shells -
First shell maximum number of electrons
A
2
17
Q
Shells -
Second shell maximum number of electrons
A
8
18
Q
Shells -
Third shell maximum number of electrons
A
8
19
Q
Periodic table electronic structure -
Period (row)
A
Number of rings
20
Q
Periodic table electronic structure -
Group (column)
A
Electrons in outer shell
21
Q
Periodic table electronic structure -
Atomic number
A
Total number of electrons
22
Q
History of the atom -
Dalton
A
All atoms look the same
23
Q
History of the atom -
Thomson
A
Plum pudding model
24
Q
History of the atom -
Rutherford
A
Nuclear model
25
History of the atom -
| Bohr
Electron shells
26
Subatomic particle -
| Protons
```
Charge = +1
Mass = 1
```
27
Subatomic particle -
| Electrons
```
Charge = -1
Mass = 1/1800
```
28
Subatomic particle -
| Neutrons
```
Charge = 0
Mass = 1
```
29
Chromatography -
| Purpose
Separate substrate from mixtures in solution.
30
Chromatography -
| Key points
```
Use a pencil to draw the line
Solvent soaks up the paper
Mixtures separate based on solubility
The number of dots is the number of substances in the mixture
The distance they travel can be compared
```
31
Separating substances key words -
| Compound
Two or more elements chemically combined
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Separating substances key words -
| Mixture
Two or more elements or compounds mixed but not reacted
33
Separating substances key words -
| Pure
Only one type of substance (molecules or atoms)
34
Separating substances key words -
| Distilation
Separation of a liquid from a mixture (evaporate -> condense)
35
Separating substances key words -
| Filtration
Separation of an insoluble solid from a solution
36
Separating substances key words -
| Crystallisation
Used to obtain pure salt from a solution by evaporation
37
Law of conservation of mass
Reactant = products
| The total mass of the reactants formed in a reaction equal to the total mass of the products
38
Periodic table -
| Lavousier
The earliest attempt. Grouped elements based on their properties into gases, non-metals and earths.
39
Periodic table -
| Dobereiner
Recognised traids of elements with chemically similar properties. Only a few worked.
40
Periodic table -
| Newlands
Law of Octaves. Similarities between every 8 elements. Only worked up to Ca.
41
Periodic table -
| Mendeleev
Left gaps, arranged elements by atomic weight and chemical properties.
42
Periodic table -
| Group 1
Name - alkali metals
Features - metal, reactive
Typical changes - +1
43
Periodic table -
| Group 7
Name - halogens
Features - non-metal, reactive
Typical changes - -1
44
Periodic table -
| Group 0 or 8
Name - noble gases
Features - gases/non-metal, reactive
Typical changes - 0
45
Periodic table -
| Lithium with oxygen
- burns red flame
| - white ash of lithium oxide
46
Periodic table -
| Lithium with chlorine
- burns red flame
| - white ash of lithium chloride
47
Periodic table -
| Lithium with water
- floats, fizzes producing hydrogen gas
| - produces colourless lithium hydroxide solution (alkali)
48
Periodic table -
| Sodium with oxygen
- burns more vigorously with yellow flame
| - white ash of sodium oxide
49
Periodic table -
| Sodium with chlorine
- burns more vigorously with yellow flame
| - white ash of sodium chloride
50
Periodic table -
| Sodium with water
- floats and melts, fizzes producing hydrogen gas
| - produces colourless sodium hydroxide solution
51
Periodic table -
| Potassium with oxygen
- burns violently with lilac flame
| - white ash of potassium oxide
52
Periodic table -
| Potassium with chlorine
- burns violently with lilac flame
| - white ash of potassium chloride
53
Periodic table -
| Potassium with water
- floats, hydrogen gas sets on fire with lilac flame
| - produces colourless potassium hydroxide solution
54
Periodic table -
| Period definition
number of rings
55
Periodic table -
| Group definintion
electrons in the outer shell
56
Periodic table -
| Structure definition
number of electrons in each shell
57
chlorine + potassium bromide
2KCL + Br (small2)
58
chlorine + potassium iodine
2KCl + I (small2)
59
bromine + potassium chloride
no reaction
60
bromine + potassium iodine
2KBr + I (small2)
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iodine + potassium chloride
no reaction
62
iodine + potassium bromide
no reaction
63
Size of atom
Larger atoms lose electrons more easily
| Smaller atoms gain electrons more easily
64
Nuclear charge
The higher the atomic number the greater the charge
65
Electronic shielding
Complete shell block the positive charge from the nucleus, the more complete shells, the more the charge is blocked.
66
Displacement reactions
A reactive element can displace a less reactive ion from a compound. So the reactive element kicks out the ion, forming a new compound, and turning the ion into and element. If the element it less reactive than the ion, then it can't displace the ion and there will be no reaction.
67
Transition metals
- metals in the 'd block' of the periodic table
- typical metals, high m.p/b.p, shiny, good conductors, malleable, ductile.
- form colourful compounds
- ions have multiple charges
- make useful catalysts
68
Structures & bonding -
| Alloy
A mixture of two or more elements, at least one of which is a metal. (brass)
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Structure & bonding -
| Covalent bond
The bond between two atoms that shares one or more pairs of electrons.
70
Structure & bonding -
| Delocalised electron
A bonding electron that is no longer associated with any one particular atom.
71
Structure & bonding -
| Gases
Substances that have no fixed shape or volume and can be compressed easily.
72
Structure & bonding -
| Giant covalent structure
A huge 3D network of covalently bonded atoms
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Structure & bonding -
| Giant lattice
A huge 3D network of atoms or ions
74
Structure & bonding -
| Intermolecular forces
The attraction between the individual molecules in a covalently bonded substance.
75
Structure & bonding -
| Ionic bond
Bonds formed by the transfer of electrons and held together by the electrostatic force of attraction between positively and negatively charged ions.
76
Structure & bonding -
| Liquids
Substances that have a fixed volume, but they can flow and change their shape.
77
Structure & bonding -
| Polymer
Substance made from very large molecules made up of many repeating units (monomers).
78
Structure & bonding -
| Solids
Substances that have a fixed shape and a volume that cannot be compressed.
79
Structure & bonding -
| States of matter
The form in which matter can exist. A substance can be solid, liquid or gas.
80
Ionic bonding -
| Ionic solid
- ions are in fixed positions in a giant lattice
- they vibrate but cannot move around
- it does not conduct electricity
81
Ionic bonding -
| Molten ionic compound
- high temperature provides enough energy to overcome the many strong attractive forces between ions
- ions are free to move around within the molten compound
- it does conduct electricity
82
Ionic bonding -
| Ionic compound in solution
- water molecules separate ions from the lattice
- ions are free to move around within the solution
- it does conduct electricity
83
Giant covalent molecules -
| Graphite
- contains covalently bonded carbon atoms arranged in layers
- no covalent bonds
- between the layers there are weak intermolecular forces
- layers can slide over eachother
- soft and slippery
- delocalised electrons allows it to conduct electricity
84
Giant covalent molecules -
| Diamond
- carbon atoms have a rigid giant covalent structure
| - hard/solid
85
Simple covalent molecules
- Have a weak intermolecular force
- low melting and boiling points
- no overall charge
- no electrical charge
- cannot conduct electricity
86
Fullerenes
- used for drug delivery, lubricants and catalysts due to large surface area
- graphene is a single layer of graphite and so one atom thick
- good electrical conductivity
87
Metallic bonding
- atoms in metals are closely packed together in regular layers
- the positively charged metal ions are held together held by a 'sea' of electrons from the outer shell of each metal atom
- good conductors of electricity and thermal energy
- delocalised electron
- layers of metal ions can slide over eachother
88
Alloys
- a mixture of 2 or more elements
- at least one is a metal
- usually harder than pure metals because the regular layers in pure metal are dissorted by the atoms of different sizes in an alloy
- no layers can slide over one another
89
Relative mass & moles -
| Mass number
Number of protons and neutrons
90
Relative mass & moles -
| Isotopes
Same number of protons, different number of neutrons
91
Relative mass & moles -
| Relative atomic mass
Mass of atom (Ar) compared to (12) C. So sodium (Na) = 23
92
Relative mass & moles -
| Relative formula mass
The total of the relative atomic masses, added up in the ratio shown in the chemical formula, of a substance
93
Relative mass & moles -
| Moles
The amount of substance in the relative atomic or formula mass of a substance in grams
94
Relative mass & moles -
| Concentration
The amount of a substance dissolved in a given volume of liquid
95
Metal oxide
Metals react with oxide to produce metal oxides. This is an oxidation reaction
96
Displacement reaction
A more reactive metal can displace a less reactive metal from a compound
97
Oxidation
Two definitions
- chemicals are oxidised if they gain oxygen in a reaction
- chemicals are oxidised if they lose electrons in a reaction
98
Reduction
Two definitions
- chemicals are oxidised if they lose oxygen in a reaction
- chemicals are oxidised if they gain electrons in a reaction
99
Acid
A chemical that dissolves in water to produce H+ ions
100
Base
A chemical that reacts with acids and neutralise them
101
Alkali
A base that dissolves in water
| produces OH- ions in a solution
102
Neurtralisation
When a neutral solution is formed from reacting and acid and an alkali.
103
pH
A scale to measure acidity/alkalinity
104
Strong acid (HT)
A strong acid is completely ionised in solution (e.g. hydrochloric, nitric and sulfuric acids
105
Weak acid (HT)
A weak acid is only partially ionised in solution (e.g. ethanoic, citric and carbonic acids
106
Potassium reaction
When potassium is added to water, the metal melts and floats. It moves around very quickly. The metal is also set on fire, with sparks and a lilac flame
107
Sodium reaction
When sodium is added to water, it melts to form a ball that moves around on the surface. It fizzes rapidly
108
Lithium reaction
When lithium is added to water, it floats. It fizzes steadily and becomes smaller
109
Calcium reaction
fizzes quickly with dilute acid
110
Magnesium reaction
fizzes quickly with dilute acid
111
Zinc reaction
bubbles slowly with dilute acid
112
Iron reaction
very slow reaction with dilute acid
113
Copper reaction
no reaction with dilute acid
114
Extracting metals -
| very unreactive metals
found naturally in the ground
| don't need extracting
115
Extracting metals -
| metals less reactive than carbon
extracted by reduction with carbon
116
Extracting metals -
| metals more reactive than carbon
extracted by electrolysis
117
Making a soluble salt
- add solid metal, metal carbonate, metal oxide or metal hydroxide to an acid
- add solid until no more reacts
- filter off excess solid
- evaporate to remove some of the water
- leave to crystallise
- remove all water in a desiccator / oven
118
Electrolysis definition
The process of splitting an ionic compound by passing electricity through it
119
Electrolyte definition
An ionic compound that is molten or dissolved in water. The ions are free to move
120
Electrode definition
An electrical conductor that is placed in the electrolyte and connected to the power supply
121
Cathode definition
The electrode attached to the negative terminal of the power supply
122
Anode definition
The electrode attached to the positive terminal of the power supply
123
Cathode descripition
- metal
- the metal if the metal is less reactive than hydrogen
- hydrogen is produced if the metal is more reactive than hydrogen
124
Anode description
- non-metal
- oxygen is produced unless the solution contains halide ions (chloride, bromide and iodide) when the halogen (chlorine, bromine and iodine) is being produced
125
Aluminium electrolysis -
| Cryolite
Aluminium oxide is dissolved in cryolite to lower it's melting point. This saves money on energy costs.
126
Aluminium electrolysis -
| Cathode
Positive Al (small3+) ions move to the cathode. Aluminium is produced Al (small 3+) + 3e = Al
127
Aluminium electrolysis -
| Anode
Negative 0 (small2-) ions move to anode. Oxygen is made. 2O (small2) = O (small2) + 4e
128
Conservation of energy
Energy is not created or destroyed, only transferred from one store to another
129
Exothermic
A reaction that transfers energy to the surroundings so the temperature of the surroundings increases, e.g. combustion and neutralisation reactions. Used in self-heating cans and hand warmers
130
Endothermic
A reaction that takes energy in from the surroundings so the temperature of the surroundings decreases, e.g. thermal decomposition. Used in sports injury packs
131
Activation energy
The energy needed for particles to successfully react
132
Breaking bonds
Energy is needed to break bonds
133
Forming bonds
Energy is released when bonds are formed
134
Exothermic energy profile
Energy released from forming bonds is greater than the energy needed to break bonds
135
Endothermic energy profile
Energy release from forming bonds is less than the energy needed to break bonds
