Topic 1- Atomic structure and the Periodic Table Flashcards
1
Q
what is the electronic structure when filling outer shells
A
2.8.8…..
2
Q
what does 2.8.8 mean
A
the maximum number of electrons that fit in each outer shell
3
Q
why do elements react
A
in order to fill out their outer shells
4
Q
what is the electron configuration of sodium, Na
A
2.8.1
they have 11 electrons
5
Q
what is the electron configuration of calcium, Ca
A
2.8.8.2
they have 20 electrons
6
Q
what is fractional distillation used for
A
to separate a mixture of liquids
7
Q
why can the mixture be separated using fractional distillation
A
because they have very different melting points
8
Q
what do you use to condense the liquid in fractional distillation
A
a fractionating column
9
Q
how do you do fractional distillation
A
- put the mixture in a flask and stick a fractionating column on top the heat it
- when the liquid with the lowest boiling point starts to evaporate it reaches the top of the column
3.it will condense and collect in a test tube - raise the temperature until the next liquid is ready
10
Q
which liquid will evaporate first in fractional distillation
A
liquid with lowest boiling point
11
Q
as the first liquid evaporates, what happens if other liquids start to aswell in fractional distillation
A
liquids with higher boiling points might also start to evaporate but the column is cooler towards the top so they will condense again
12
Q
what is crystallisation used to separate
A
soluble solids from solutions
13
Q
how do you carry our crystallisation
A
- pour the solution into an evaporating dish and gently heat the solution using a bunsen burner with a water bath over it and the dish on top(becomes more concentrated as it evaporates)
- once some has evaporated or when you start to see crystals start to form, remove the dish from the heat and leave it cool
- the salt should start to form crystals as it becomes insoluble in the highly concentrated solution
- filter the crystals out of the solution and leave them to dry
14
Q
what happens when the solution starts to evaporate
A
the solution becomes more concentrated
15
Q
how do you do evapoartion
A
- pour the solution into an evaporating dish
- slowly heat the solution. the solvent will evaporate and the solution will get more concenrtated
- crystals will start to form
- keep heating the evaporating dish until all you have left are dry crystals
16
Q
what is evaporation used for
A
separate a soluble salt from a solution
17
Q
what does filtration separate
A
insoluble solids from solutions
18
Q
what happens in filtration
A
when the solution is poured, the solid gets trapped in the filter paper and the liquid goes through
19
Q
what is simple distillation used for
A
to separate out solutions
20
Q
how does simple distillation work
A
- the solution is heated. the liquid with the lowest boiling point evaporates first
- the vapour is then cooled, condensed and is collected
- the rest of the solution is left
21
Q
what is the problem with simple distillation
A
it only works with to separate liquids with very different boiling points- if boiling point goes higher they will mix again
22
Q
what is an example of how simple distillation is used
A
to get pure water from sea water
23
Q
what is the difference between simple and fractional distillation
A
- simple only separates one fraction(Liquid) but fractional separates multiple
- fractional uses a fractionating column
24
Q
what is rock salt
A
a simple mixture of salt and sand
25
what 4 things do you do to separate rock salt
1. grinding
2. dissolving
3. filtering
4.evaporating
26
how do you separate rock salt
1. GRINDING grind the mixture to make sure salt crystals are small, so will dissolve easily
2. DISSOLVING put the mixture in water and stir. the salt will dissolve the sand wont
3. FILTERING filter the mixture. the sand will collect in the paper. the salt passes through as part of the solution
4. EVAPORATING evaporate the water from the salt so it forms dry crystals (or crystallisation if you want big ones)
27
what is a mixture
two or more element or compounds not chemically bonded together
28
what happens to the chemical properties of the substances in a mixture
the chemical properties of each substance in the mixture is unchanged
29
how do you separate a mixture
using physical methods
30
are mixtures easily separated
yes
31
what does soluble mean
can be dissolved(a solid)
32
what is an example of a soluable substance
sugar, salt
33
what does insoluble mean
does not dissolve
34
what is an example of insoluble substances
sand
35
what does miscible mean
liquids that dissolve in each other
36
what is residue
solid collected in the filter paper
37
what is the filtrate
liquid/solution that runs through the filter
38
what is immiscible
not soluble, don't mix
39
what does chromatography separate
separates mixtures(dyes in ink)
40
how do you set up a chromatography
take a piece of filter paper and draw a pencil line near the bottom
place a dot of ink on the line
41
how do you do chromatography
1. place the prepared filter paper in the solvent(water)
2. as the solvent travels up the paper, it drags the different dyes with it, more soluble dyes work best
42
in chromatography, what happens to soluble dyes
it will travel quicker and further
43
what is the end result of the chromatography called
a chromatogram
44
what is an ion
an atom with a charge(gained or lost electron)
45
what is the ion for each group
1= +
2= +2
3=+3
4= don't make ions
5=3-
6= 2-
7= -
0= already stable- don't make ions
46
what is the ion of sodium, Na
Na +
47
what is the ion for sodium electron configuration
[2.8]+
11 electrons-lost an electron from the outer shell
48
when balancing equations, what must ALWAYS be the same
same number of atoms on both sides
49
what does a molecular formula show
what atoms are in a substance
50
which side of a formula are the reactants on?
Products?
reactants- left
products- right
51
ethane +oxygen ---> carbon dioxide + water
which are Products?
reactants?
products- carbon dioxide, water
Reactants- ethane, oxygen
52
what is the law of conservation of mass
total mass of products formed is ALWAYS equal to the total mass of reactants
53
what is an isotope
atoms of the same element with a different number of NEUTRONS and the same number of PROTONS
54
what is the only thing that affects what an element is
the atomic number
55
Isotopes have the same ----- number but different ------ numbers
isotopes have the same atomic number but different mass numbers
56
what are the chemical properties of isotopes
- isotopes of an element have the same chemical properties because electron arrangement is the same
57
what are the physical properties of an isotope
isotope of an element have different masses due to having more or less neutrons in the nucleus
58
what is an atom
the smallest part of an element
59
what is an element
a substance with only one type of atom
60
what is a compound
substance with 2 or more elements chemically bonded
61
what are the vertical columns called ^
groups
62
what are the horizontal rows called >
periods
63
what subatomic particles are found in the nucleus
protons and neutrons
64
what subatomic particles are on the outside in shells
electrons
65
what is the radius of a nucleus
1x10 ^-14
66
what does the nucleus contain
protons and neutrons
67
where is the nucleus located
in the centre of the atom
68
what is the charge of the nucleus
positive charge due to protons
69
where is the mass of the atom concentrated
in the middle
70
how many electrons and protons are in an atom
the same
71
what is the charge of an atom? why?
neutral- they have the same number of proton and electrons and have opposite charges so cancel out
72
where are electrons in an atom
move around the neutron in electron shells
73
23
Na
11
which one is the mass number
the top one
74
what is the mass number
total number of protons and neutrons
75
23
Na
11
which is the atomic number
the bottom one
76
what is the atomic number
how many protons there are
77
what is the relative charge of the neutron
0
78
what is the relative charge of the proton
+1
79
what is the relative charge of the electron
-1
80
what is the relative mass of the neutron
1 mass unit
81
what is the relative mass of the electron
virtually no mass
1/1840 mu
82
what is the relative mass of the proton
1 Mass unit (MU)
83
how do you find the number of protons
atomic number
84
how do you find the number of neutrons
mass number- proton number
85
how do you find the number of electrons
number of protons
86
what happens during a chemical reaction
always involve the formation of one or more new substances and often involve a detectable energy change
87
how can compounds be represented
by formula
88
what is the radius of an atom
0.1 NM
or 1x10^-10
89
how is the modern periodic table laid out
in order of increasing atomic number
90
because of how the modern periodic table is laid out what does it mean
there are repeating patterns in their properties
91
where are metals found on the periodic table
left
92
where are the non metals found on the periodic table
right
93
what are the vertical columns called
groups
94
what are the horizontal rows called
periods
95
what does the group number tell you
how many electrons there are in there outer shells
96
what do the groups in the periodic table allow you to do
you can predict properties of other elements in that group e.g group 1 metals all react in similar ways
97
what are the group 0 elements known as
noble gases
98
are the noble gases (group 0) reactive
no they are unreactive
99
why are the noble gases unreactive
they are unreactive because they have a full outer shell- 8
100
what does inert mean
don't react at all
101
what is different between helium and the rest of the noble gases
it only has 2 in its outer shell- but it still has a full outer shell
102
what are the trends of group 0 elements (noble gases)
- increase in boiling point down the group
- increase in relative atomic mass down the group
103
why does the boiling point increase down the group in group 0 elements
due to an increase in the number of electrons in each atom leading to greater intermolecular forces which need to be overcome
104
ESQ- neon is gas at 25 'C. Predict what state helium is at at this temperature
- helium is higher on the periodic table so has a lower Boiling point
- must be a gas
105
what are the group 0 elements at room temperature
colourless gases
106
are the group 0 elements flammable
non- flammable
107
what are the group 7 elements called
the halogens
108
why do the group 7 elements react similarly
they all have 7 electrons in their outer shells
109
are the group 7 elements metals or non metals?
non metals
110
what do the group 7 elements consist of
molecules made of pairs of atoms
111
what are the trends of group 7 elements
- melting point, boiling point and relative atomic mass increase down the group
- the reactivity decreases down the group
112
why does the reactivity decrease down the group of the group 7 elements
it is harder to gain extra electrons because the outer shells are further from the nucleus so it cannot easily gain an electron
113
how can the halogens also get a full outer shell
the atoms can share electrons via covalent bonding with other non metals to achieve full outer shells
114
what bonding
is it called when nonmetals react with metals
ionic bonding
115
------ reactive Halogens will ------- ----- reactive ones from an ------- solution of its -----
more reactive halogens will displace less reactive ones from an aqueous solution of its salts
116
what is formed when the halogens react
compounds that all have simple molecular structures
117
what is the difference between group 1 metals and transition metals
- group 1 metals are much more reactive- react more vigorously with water, oxygen
- much less dense, strong and hard than transition metals
- group 1 metals have lower melting points
118
what happens when group 1 elements react with water
they react vigorously to produce hydrogen gas and metal hydroxide
119
what is produced when a group 1 element reacts with water
hydrogen gas and metal hydroxide
120
what is the equation for a reaction between a group 1 element and water
metal + water ---> metal hydroxide +hydrogen
121
what happens down the group when group 1 elements react with water
- the lower down the group the more vigorous the reaction
- the amount of energy given out by the reaction increases
122
what happens when group 1 elements react when heated with chlorine
vigorously react when heated with chlorine gas to form white metal chloride salts
123
what is the equation for the reaction between group 1 elements and chlorine
metal+ chlorine --> metal chloride
124
what happens down the group when group 1 metals react with chlorine
- the reaction increases and becomes more vigorous
125
what is produced when group 1 elements react with oxygen
metal oxide
126
what does lithium produce when reacting with oxygen
lithium oxide
127
what does sodium produce when reacting with oxygen
sodium oxide and sodium peroxide
128
what does potassium produce when reacting with oxygen
potassium peroxide and potassium superoxide
129
what are group 1 elements also known as
alkali metals
130
how many electrons are in the alkali metals outer shells
1
131
what are the properties of the alkali metals(group 1)
- soft
- have low density
- the first 3 in the group are less dense than water
132
what does it mean if the alkali metals have 1 electron in their outer shell
- they are very reactive
- have similar properties
133
what are the trends down the group for the alkali metals
- increases in reactivity
- lower melting and boiling points
- higher relative atomic mass
134
why does the reactivity increase down the group in the alkali metals
outer electron is more easily lost as attraction between nucleus and electrons decrease - more shielding because there is more shells
135
what are the transition metals found on the periodic table
in the centre between group 2 and 3
136
what are the physical properties of the transition metals
typical metal- dense, strong, shiny, conduct
137
do the transition metals all have similar properties
yes
138
what are the chemical properties of the transition metals
- useful as catalysts
- make colourful compounds
- ions with different charges
139
what are catalysts
speed up reactions
140
how do you work our relative atomic mass
(isotope abundance x mass number)
/sum of abundance(all isoptopes)
141
ESQ 14 13 12
C C C
1% 3% 96%
what is the relative atomic mass
(14x1)+(13x3)+(12x96)/100
= 12.05
142
what is a metal
element that reacts to form positive ions
143
what is a non metal
elements that do not react to form positive ions
144
why do metals form positive ions
there is not much energy needed to remove the electrons so it is feasible for the elements to react to form positive ions with full outer shells
145
why do non metals not form positive ions
it is far more feasible for them to either share or gain electrons to get a full outer shell, it is harder to remove electrons
146
what are the physical properties of metals
- strong- malleable, ductile(can be wires)
- great at conducting heat and electricity
- high boiling and melting points
147
why do metals have similar physical properties
all metals have metallic bonding which cause them to have similar
148
what are the physical properties of non metals
- dull looking and more brittle
- don't conduct electricity generally
- often lower density
- aren't always solid at room temperature
149
what was the order of the discovery of the subatomic particles
1. electrons- JJ Thompson
2. nucleus- Rutherford
3. protons
4. neutrons- Chadwick
150
what was the first model of the atom
plum pudding model
151
who created the plum pudding model
JJ Thompson
152
what is the plum pudding model
suggested the atom is a ball of positive charge with negative electrons embedded in it randomly
153
who created the nuclear model
Rutherford
153
who did the alpha particle scattering experiment
Geiger and Marsden(students of Rutherford
154
what was the alpha particle experiment
- they took a piece of gold foil and fired alpha particles at it. most particles passed through but a few were reflected by the centre and small number were repelled back to source
155
what did the alpha particle experiment conclude
- the mass of the atom was concentrated at the centre(nucleus) and it was charged
- rest of the atom was empty space
156
how did Niels Bohr alter the nuclear model
suggested that electrons orbit the nucleus at specific distances
157
what did experiments lead to after Niels Bohr
the idea that the positive charge of any nucleus could be subdivided into smaller particles, called protons
158
what did the experimental work of Chadwick find
the existence of neutrons in the nucleus- 20 years after the nucleus was accepted
159
how did Dalton order the periodic table
elements by weight
160
how did newlands order the periodic table
ordered the elements into columns of order of atomic mass, in rows of 8, patterns didnt always work
161
how did moseley order the periodic table
by atomic number
162
what is the order of scientists who altered the periodic table
1. Dalton
2. Newland
3. Mendeleev
4. Moseley
163
how did Mendeleev alter the periodic table
left gaps for elements that he thought had not been discovered and in some places changed the order based on atomic weight
- the elements with properties predicted by Mendeleev were discovered and filled the gaps
164
how did scientist try to order the elements before the discovery of the protons
in order of atomic number
165
what was wrong with the early periodic table
was incomplete, some elements were placed in inappropriate groups if the order of atomic weights were followed
166
what is the modern periodic table based on
Mendeleev's ideas plus new elements
