Topic 1 Atomic Structure And Periodic Tablr Flashcards
(111 cards)
1
Q
Relative mass of a proton
A
1
2
Q
Relative mass of a neutron
A
1
3
Q
Relative mass of an electron
A
Very small
4
Q
What is mass of electrons and neutrons and protons given in relation to
A
The mass of a proton
5
Q
Relative charge of a proton
A
+1
6
Q
Relative charge of a neutron
A
0
7
Q
Relative charge of an electron
A
-1
8
Q
What does the nucleus of atoms contain
A
Protons and neutrons
9
Q
How much of an atom is the nucleus
A
1/10000th
10
Q
Where is most of the mass of an atom contained
A
In the nucleus
11
Q
What does the atomic number represent
A
Number of protons
12
Q
What determines which element an atom is
A
How many protons it has
13
Q
In an atom are the number of protons and electrons equal
A
Yes
14
Q
What does the mass number represent
A
Number of protons + number of neutrons
15
Q
Which number is the mass number on periodic block
A
The top one
16
Q
Which number is the atomic number on periodic block
A
The bottom one
17
Q
What are isotopes
A
Atoms with the same number of protons, but a different number of neurons
18
Q
Out of mass numbers and relative atomic mass which one is an interference
A
Mass numbers
19
Q
What is relative atomic mass
A
The average mass of atoms of an element taking into account the mass and amount of each isotope it contains
20
Q
Formula for relative atomic mass (Ar) r is smaller
A
Total mass of all atoms of element / total number of atoms of that element
21
Q
What is an ion
A
An electrically charged particle containing different number of protons and electrons
22
Q
Are ions particles with an electric charge
A
Yes because they have different numbers of protons and electrons
23
Q
What do simple ions (other than hydrogen) have the same electronic structure as
A
Elements in group 0
24
Q
What are simple ions
A
Those made from single atoms
25
Why is the hydrogen ion not have the electrical structure of a noble gas
Because it doesn’t have any electrons at all making it very special with special properties, these ions are also responsible for the behaviour of acids
26
Who proposed the idea that everything was made out of particles was atoms and when and what was the difference between what we know now
By John Dalton in the early 1800s.
People thought atoms were the smallest possible particle.
27
Who and when discovered the electron and how and what was the suggested model of an atom then.
By J.J. Thompson in 1897.
Through experiments on the conduction of electricity through gases.
He created the ‘plum pudding’ where the atom was a ball of positive charge and electrons were spread through the atom
28
When and by who was the ‘plum pudding’ model replaced by the nuclear model
In 1911, by work from Hans Geiger, Ernest Mardsen working Ernest Rutherford.
29
What causes the nuclear model to replace the ‘plum pudding’ model
The scientists (state names and year) involved fired alpha particles at a very tiny think piece of gold foil. They expected the particles to pass straight through the foil but a tiny fraction were deflected or even bounced back. This did not fit with the ‘plum pudding’ model as it would suggest all of them pass. Therefore Rutherford worked out the scattering of some of the alpha particles meant that there must be a tiny, positive nucleus at the centre of each atom
30
What did Neils Bohr do and when
In 1913, he adapted the nuclear model to suggest that the electrons moved in stable orbits at specific distances from the nucleus called shells. Bohr’s theoretical calculations agreed with observations from experiments
31
What happened in 1932 in terms of discovery of atom
Scientists realised that there was some mass in atoms that could not be explained by this model and in 1932 James Chadwick discovered a new particles inside the nucleus that had the same mass as a proton but no electrical charge which was named neutron
32
What shows how scientific models and theories develop over time by new discoveries and experiments
Development of ideas about atomic structure
33
What is the definition of an element
A substances containing only one type of atom; a substance that cannot be broken down into simpler substance by chemical methods
34
Make sure to know the line between metals and non metals and difficult to classify
Do this for future Nikolai
35
What happens when metals react with metal
No reaction because both metals cannot lose electrons
36
Difference between metals and non-metals melting and boiling points
High for metals and low for non-metals
37
Difference between conductivity between metals and non-metals
Metals are thermal and electrical conductors while non-metals are thermal and electrical insulators (except graphite)
38
Difference between density between metals and non-metals
Metals have high density and non-metals have low density
39
Appearance difference between metals and non metals
Metals are shiny when polished and non-metals are dull
40
What happened to non-metals when reached with metals
Reach to form negative ions in ionic compounds
41
What happens to metals when reacted with non-metals
React to form positive ions in ionic compounds
42
What happens when non-metals react with non-metals
They react to form molecules and they share electrons
43
What are the acid-base properties of oxides of metals
Metal oxides are basic
44
What are the acid-base properties of oxides of non-metals
Non-metal oxides are acidic
45
What is a compound
A substance made from different elements chemically bonded together
46
What are the columns in the periodic table called
Groups
47
What are the rows in the periodic table called
Periods
48
What are the elements placed in order of in the periodic table
Increasing atomic number (number of protons)
49
What makes what periods represent in periodic table
Amount of shells
50
What makes the elements in the same group share
All have the same amount of electrons in the outer shell (except for helium in group 0 which has 2 instead of 8)
51
Noble gases properties
All colourless gases
Boiling points increase as you go down (from -269 to -62)
The atoms get heavier as you go down the group
They are very unreactive because of their atoms having stable electron arrangement with full outer shells
52
Examples or noble gases
Helium and neon
53
What group is the noble gases
Group 0
54
What group is the alkali metals
Group 1
55
Examples of alkali metals
Lithium, sodium and potassium
56
Properties of alkali metal
All soft and can be cut with knife
Very reactive
Silver-grey metals
Mass of atoms go up as you go down
Melting points go down as you go down (180-28)
Density increases as you go down
Densities pretty low for metals
More reactive as you go down
57
Where are alkali metals stored and why
In bottles of oil to stop them reacting with water and oxygen because they are very reactive because they only have 1 outer shell electron which they can lose easily
58
Properties of compounds made from Group 1 metals
They are ionic
Are white solids
Dissolve in water to form colourless solutions
59
Why does the reactivity of alkali metals increase as you go down the group
Because the further down the group, the further away the outer electron is from the nucleus as the atoms get bigger with more shells. This means the outer electron is less strongly attached to the nucleus and easier to lose. The easier the electron is to lose, the more reactive the alkali metal
60
Description of reaction between lithium and water
Fizzes and moves on the surface of water
61
Description of reaction of potassium with water
Fizzes, melts, burns with lilac flam and moves on the surface of the water
62
Description of Caesium reaction with water
Explosive reaction
63
What group are the halogens
Group 7
64
Example of halogens
Fluorine, chlorine, bromine and iodine
65
What are diatomic molecules
Molecules containing two atoms
66
What molecules are the particles all group 7 elements
Diatomic molecules such as Br2
67
Why are halogens reactive
Because they only need to gain one electron and to gain a stable electronic structure of a full outer shell
68
Properties of halogens
Reactive
Relative mass of molecules increase as you go down
Melting point increase as you go down (-220 to 114 from 1-4)
Boiling point increases as u go down (-188 to 184 from 1-4)
They are all toxic
The further u go down the less reaction they get
69
How to test for reactivity series for halogens
By displacement reactions as more reactive will displace the less reactive
70
Why does the reactivity of halogens go down as you go down the group
Halogens need to gain one electron in order to get a noble gas electronic structure. The further down the group, the electron gained will enter an energy level further away from the nucleus as the atoms get bigger. This means that the electron gained is less strongly attracted to the nucleus and harder to gain. The harder the electron is to gain, the less reactive the halogen.
71
Why don’t people do experiments with fluorine (highest gas in the halogens group)
Because it is very reactive and toxic
72
What are halides
Compounds made from group 7 elementes
73
What was the periodic table first order by
Atomic weight rather than atomic number which we do now
74
Who spotted that the properties of elements seemed to repeat every eighth element when placed in order of atomic weight and what was it referred to and another on one of his successes
John Newlands spotted it and he called it the ‘law of octaves’ and he has lithium, sodium and potassium in the same group which have very similar properties
75
Major problem with Newlands’ table
He had copper in the same group as lithium, sodium and potassium and copper had very different properties to those metals such as not reacting with water while the other three react vigorously with water
76
What did Mendeleev
77
What did Mendeleev do similarly to Newlands table
He placed them in order of atomic weight (moslty
78
What two things did Mendeleev crucially do differently than Newlands table
1. He left gaps for elements he predicted had yet to be discovered and predicted properties of these elements
2. He was prepared to alter slightly the order of the elements if he though it fitted with the properties better so that some elements such as iodine and tellerium were swapped even if the order of the atomic weight wasn’t stayed true to, so that the properties of groups remained very similar
79
Were Mendeleev predictions correct
Almost fully correct
80
Why did Mendeleevs ideas become accepted
Because over the next years the elements he predicted were very similar to what he predicted and almost fully correct such as for germanium
81
What is the definition of a mixture
More than one substance that are not chemically joined together
82
What is the difference in the proportions between compounds and mixtures
Each compound has a fixed proportion of elements with a fixed formula while in mixtures there can be any amount of each substance in the mixture
83
Difference in separation of mixtures and compounds
Compounds can only be separated back into elements by chemical reaction because the elements are chemically joined while in a mixture no chemical reaction is needed as the substances in the mixture are not chemically joined and can be separated by physical methods like filtration or distillation
84
Sodium properties
Very reactive, dangerous, grey metal that reacts vigorously with water
85
Chlorine properties
A pale green, toxic gas that is very reaction
86
Are the properties of chlorine and and sodium the same in a mixture
Yes
87
What happened when you heat sodium with chlorine and properties
Creates the compound sodium chloride which has very different properties than both of them as sodium chloride is a white solid that is not very reaction and is safe to eat.
88
Why is sodium chloride very difficult to break down into elements
Because the sodium and chlorine are chemically joined together
89
Definition of solute
The solid substance that dissolves in a solvent
90
Definition of solvent
The liquid that a solute dissolves in
91
Definition of solution
A solute dissolved in a solvent
92
Definition of soluble
When a substance will dissolve in a solvent
93
Definition of insoluble
When a substance does not dissolve in a solvent
94
What is filtration used to separate
An insoluble solid from a liquid
95
Describe the process of filtration
The mixture is poured through a funnel containing a piece of filter paper. The liquid (filtrate) passes through the paper and the solid (residue) remains on the filter paper
96
What is evaporation used to separate and example
A dissolved solid from the solvent it is dissolved in for example used to separate salt from water
97
Describe process of evaporation and
The mixture is placed in an evaporating dish and heated until all the solvent has evaporated or boiled, leaving the solid in the evaporating basin
98
Describe the process of crystallisation
The mixture is heated to boil off some of the solvent to create a hot saturated solution. A saturated solution is one in which no more solute can dissolve at that temperature. As it cools down, the solute becomes less solute and so cannot remain dissolved, so some of the solute crystallises out of the solution as crystals. The crystals can then be separated from the rest of the solution by filtration.
99
What does crystallisation used to separate and example
Dissolved solid from the solvent. For example to separate copper sulfate crystals from a solution of copper sulfate
100
What does simple distillation separate and example
The solvent from a solution for example pure water from sea water
101
Describe the process of simple distillation
The mixture is heated and the solvent boils. The vaporised solvent passes through a water cooler condenser where it cools and condenses. The condenser directs the condensed solvent into a container away from the original solution.
102
Which group can act as catalysts
Group 3
103
What does fractional distillation separate
Miscible liquids and also works with liquids that have different boiling points
104
Definition of miscible
Liquids that mix together
105
Describe fractional distillation
The apparatus used is similar to that for simple distillation but a long column (called a fractional column) is used to help separate different liquids as they boil and it often contains glass beads.
106
How is fractional distillation used in industry
It is used in crude oil, the whole mixture is vaporised and then condensed in a fractionating column, which is hot at the bottom and cold at the top. The liquids will condense at different height in the fractionating column.
107
What does a separating funnel separate
Immiscible liquids.
108
Example of immiscible liquids
Oil and water
109
Describe the process of a separating funnel
The liquids form two layers and the bottom layer can be removed using the tap at the bottom of the funnel. The liquid with the greater density is the lower layer
110
What is paper chromatography used to separate
Mixtures of substances dissolved in a solvent
111
Describe paper chromatography
A piece of chromatography paper with the mixture on is placed upright in a beaker so that the bottom of the paper is the solvent. Over time the solvent soaks up the paper. The substances move up the paper at different speeds and so are separated.
