Chemistry Mock exam Paper one Flashcards
1
Q
In a periodic table where are metals and non- metals
A
Metals are on the left hand side and non- metals are on the right
2
Q
Compound
A
A substance that contains two or more atoms which have been bonded together in a chemical reaction
3
Q
An ion
A
A charged particle formed when an atom, or a group of atoms lose or gain their electrons
4
Q
Reactants
A
Substances that react together in a chemical reaction
5
Q
Products
A
They join the atoms back in a different way to form products
6
Q
Solid closeness of particles
A
Very close
7
Q
Liquid closeness of particles
A
Close
8
Q
Gas closeness of particles
A
Far away
9
Q
Solid arrangement of particles
A
Regular pattern
10
Q
Liquid arrangement of particles
A
Randomly arranged
11
Q
Gas arrangement of particles
A
Randomly arranged
12
Q
Solid movement of particles
A
Vibrate around a fixed position
13
Q
Liquid movement of particles
A
Move around eachother
14
Q
Gas movement of particles
A
Move quickly in all directions
15
Q
Solid energy of particles
A
low energy
16
Q
liquid energy of particles
A
Greater energy
17
Q
Gas energy of particles
A
Highest energy
18
Q
Evaporation
A
Particles leave a liquid from its surface only, They rise to the surface and escape to the surroundings, forming a gas.
19
Q
Condensation
A
Condensation is the change of the physical state of matter from gas phase into liquid phase, and is the reverse of vapourisation. The word most often refers to the water cycle.
20
Q
Atoms’ nucleus
A
Atoms contain a nucleus which contains protons and neutrons
21
Q
The electrons
A
Move around the nucleus in electrons shells
22
Q
Electron’s charge
A
Electrons charge is negative and tiny but they cover up of space.,
23
Q
Element
A
A substance made up of atoms that all have the same number of protons in their nucleus
24
Q
isotopes
A
Are different forms of the same element which have the same number of protons but different atomic mass and.a different number of neutrons
25
relative atomic mass calculation
Sum of (isotopes abundance or percentage x isotope mass number divided by sum of all the percentages of all the isotopes
26
Making bonds
Involves giving atoms away, taking or sharing electrons- only electrons are involved
27
Compound consisting of non-metal and metal atoms
Consists of ions
28
Ionic bonding
The opposite charges of the ion means that if they're strongly attracted to eachother
29
Non metal compound
Consists of molecules
30
Covalent bonding
Each atom shares an electrons with another atom
31
Filtration
Can be used if your product is an insoluble solid that needs to be separated from a liquid reaction mixture- also be used for purification of water
32
Crystallisation
Pour the solution into an evaporating dish and gently heat the solution. Some of the solvent will evaporate and the solution will get more concentrated
33
Distilisation
Distilisation is used to separate mixtures which contain liquids- simple and fractional
34
Simple distillation
Used to separate out a liquid from its solution
35
Fractional distillation
If youve got a mixture of liquids you can separate it
36
Plum pudding model Person
JJ Thompson concluded form his experiments that atoms weren't solid spheres measurements of charge and mass showed that an atom must contain even smaller.
37
Plum Pudding model
Showed the atom as a ball of positive charge with electrons stuck in it
38
Nucleus model
Tiny, positively charged nucleus at the centre where most of the mass is concentrated, cloud of negative electrons surround the nucleus- a lot of empty space
39
electron shells
max number 2, 8, 8
40
Mendeleev
Put the elements in the order of their atomic mass but didn't switch that order. Gaps were left to make sure that elements with similar properties stayed in the same groups.
41
Periodic table arrangement
Non-metals are on the right, metals are on the left, order of their increasing atomic number (proton)
42
Metals
Elements which can form positive ions
43
Non metals
Don't generally form positive ions when they react
44
Metals to the left electrons'
Don't have many electrons to remove and metals towards the bottom have outer electrons which are a long way from the nucleus- weaker attraction
45
Non metals' attraction
They have lots of electrons to remove to get a fuller outer Sheller towards the top- electrons are close to the nucleus meaning they have a stronger attraction
46
Metal's properties
Strong, malleable, good at conducting heat and electricity and have high melting points
47
Non-metal's properties
Dull looking, more brittle, aren't always solids, don't generally conduct electricity
48
transition metals
Centre of the periodic table, typical metals have the properties of a normal metal- very dense and shiny.
49
Transition metals special properties
They have more than one ion, often coloured, they also make good catalysts
50
Group 1 elements
All have one outer electron in their outer shell, makes them very reactive- all soft and have low density
51
Increasing reactivity- group 1 elements
Outer electron is easily lost as the attraction between the nucleus and electron decreases as the electron is further away from the nucleus
52
Group 1 reacting with water
React vigourously to produce hydrogen gas, the more reactive down the group the more violent the reaction is
53
Group 1 reacting with chlorine
React vigorusly with chlorine gas to from white metal chloride salts
54
Group 1 reacting with oxygen
Form a metal oxide.
55
Group 7 elements
The halogens, become less reactive, harder to gain an extra electron because the outer shell's further away from the nucleus
56
group 7 properties
Have higher melting points, having higher relative atomic masses
57
Halogens form ionic bonds with metals
Form 1-ions called halides
58
Displacement reaction
Can occur between a more reactive halogen and the salt of a less reactive one
59
Group 0 elements
Called the noble gases, all have eight electrons in their outer energy level.
60
Group 0 electron shell stable
Energetically stable don't have to give up or gain electrons to become more stable- don't react with a lot
61
Boiling points of group 0
The boiling points increase as you go further down the group because of the number of electrons leading to greater intermolecular forces
62
Ions
Charged particles they can be single atoms or groups of atoms
63
Atoms with full outer shells
They are more stable
64
Metals forming ions
They gain electrons and therefore become positive
65
Non metals forming ions
They gain electors into their outer shell and become negative
66
Group 1, 2, 6, 7
Most likely to form ions
67
Group 1 and 2 elements
They are metals and they lose electrons to form positive ions
68
Group 6 and 7 are non-metals
They gain electrons to form negative ions
69
Ionic compounds
Have a structure called a giant lattice
70
Giant ionic lattice
Form a closely packed negative lattice and there are very strong electrostatic forces of attraction between oppositely charged ions in all directions
71
Ionic compound properties
Hight melting points, high boiling points due to many strong bonds between the ions- contain a lot of energy
72
Simple molecular substances
Made up of molecules containing a few atoms joined together by covalent bonds
73
Polymers
Long chains of repeating units
74
Allotropes of carbon
Different structual forms of the same element in the same physical state
75
Diamond is very hard
Giant covalent structure, each form 4 covalent bonds - doesn't conduct electricity as it has no free electrons or ions
76
Graphite contains sheets of hexagons
In each carbon atom only forms three covalent binds creating sheets of carbon atoms arranged in hexagons
77
electrolysis
Electrolysis is the process by which ionic substances are decomposednto simpler substances when an electric current is passed through them. Electricity is the flow of electrons or ions.
78
Accuracy
A measurement is considered accurate if it is judged to be close to the true value
79
Precision
Precise measurements are ones in which there its very little spread
80
Reactants and products in a chemical equation
Reactants go on the left, products go on the right
81
The conservation of mass
Mass is near lost or gained, the total mass of products is always equal at the end of the reaction and at the beginning
82
The empirical formula
The empirical formula of a compound is the simplest whole number ratio of atoms of each element in the compound.
83
Reacting mass calculations
Example: When 12 g of carbon is burned in air, 44 g of carbon dioxide is produced. What mass of carbon is needed to produce 11 g of carbon dioxide?
```
12 divided by 44
11 x (12 divided by 44)
```
84
Reacting mass calculations with balanced equations
Balance the equation,
| unknown mass = known mass ÷ total Mr of known substance × total Mr of unknown substance
85
The Ph scale
A meaner of how acidic or alkaline a solution is
86
The lower the Ph is...
The more acidic it is
87
The higher the Ph
The more alkaline it is
88
A natural substance has
PH 7
89
How can you measure the PH of a solution
By using an indicator which is a dye changing colour depending on whether its above or below a certain Ph
90
A ph probe
Can be used the measure the ph electronically
91
An acid
A substance that forms aqueous solutions with a ph of less than 7
92
A base
A substance with a ph greater than 7
93
An alkali
A base that dissolves in water to form a solution with a ph greater than 7
94
PH 7
Neutral
95
Neutralisation
The reaction between acids and bases
96
Tiltrations
Allow you to find out exactly how much acid Is needed to neutralise a quantity of alkali
97
Equipment used for tiltration
Pipette and pipette filller- add a set volume of alkali to the conical flask
98
Strong acids
Ionise completely in water
99
Weak acids
Do not fully ionise in solution
100
Ionisation of a weak acids
Is a reversible reaction
101
If the concentration of H + ions is higher
The rate of reaction is faster
102
Strong acids will be more reactive than...
Weak acids with the same concentration
103
What is Ph the measure of?
the concentration in hydrogen ions
104
For every decrease of 1 on the ph scale
Means the concentration of h+ ions increases by a factor of 10
105
Basic equation for the concentration changes
Factor. H+ ion concentration changes by = 10- (to the power of whatever concentration for example if ph falls from 7 to 4 the difference is -3-- 10-(-3)
106
The reactivity series
Lists metals in order of their reactivity towards other substances
107
Metals reactivity
Depends by how easily they lose their electrons
108
The higher up the reactivity series..
The more positive ions
109
The speed of the reaction is indicated by?
By the rate at which the hydrogen bubbles are given off
110
Oxides
Common metals react with oxygen
111
reduction
The reaction that operates a metal from its oxides called a reduction reaction
112
Oxidation
Gain of oxygen
113
Metals can be extracted from their ores using...
reduction or carbon
114
oxides and ores
Often the ores that the metals need to be extracted from
115
Metals higher than carbon
need to be extracted by electrolysis
116
Metals below carbon
Need to be extracted through reduction or carbon
117
A loss of electrons
Oxidation
118
Gain of electrons
Reduction
119
Redox reactions
Are displacement reactions
120
A more reactive metal...
Will displace a less reactive metal from its compound
121
Metal ion in displacement reactions
Metal ions always gain electrons- they are reduced.
122
Metal atom in displacement reactions
Always loses the electrons- they oxidise
123
Exothermic
Transfers energy to the surroundings, usually by heating- rise in temperature
124
Endothermic
One which takes in energy from the surroundings and falls in temperature
125
Bond breaking
Endothermic
126
Bond formation
exothermic
127
An electrochemical cell
Basic system made up of two different electrodes in contact with an electrolyte
128
Electrolyte
Is a liquid that contains ions which react with electrodes
129
Fuel cell
An electrical cell thats supplied with a fuel and oxygen and uses energy from the reaction between them to produce electrical energy
