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GCSE Chemistry > Topic 1- Key Concepts Of Chemistry > Flashcards

Topic 1- Key Concepts Of Chemistry Flashcards

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1
Q

How many different types of elements are there that humans have discovered ?

A

118

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2
Q

What are atoms ?

A

the smallest pieces of an element that can exist

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3
Q

What is Fe ?

A

Iron

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4
Q

What is the element Co ?

A

Cobalt

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5
Q

What is the element oxygen ?

A

O

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6
Q

Atoms of different elements can be combined together to create what ?

A

compounds

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7
Q

How are the formula of compounds made ?

A

By combining the chemical symbols of the elements that combine to make them

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8
Q

Combining different atoms creates what ?

A

different compounds

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9
Q

What does every compound contain ?

A

at least 2 different elements.

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10
Q

Combining sodium (Na) atoms and oxygen (O) atoms produces what ?

A

sodium oxide

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11
Q

What is the formula of sodium oxide ?

A

Na2O

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12
Q

What are the key features of a chemical reaction ?

A

Compounds are broken up or formed
At least 1 new substance is formed
Measurable energy change
No atoms are created or destroyed

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13
Q

Where are the reactants in an equation ?

A

left hand side

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14
Q

Where are the products of an equation ?

A

Right hand side

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15
Q

Whats the word equation for sodium + oxygen ?

A

sodium + oxygen → sodium oxide

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16
Q

What is the balanced symbol equation for sodium oxide ?

A

4Na + O2 → 2Na2O

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17
Q

In 1803 what did john Dalton suggest ?

A

first suggested that all matter is made of atoms and that atoms cannot be split.

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18
Q

How did scientists improve daltons original model of an atom .

A

with the discovery of sub-atomic particles.

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19
Q

In 1897, an English physicist called what discovered what ?

A

J. J. Thomson discovered electrons

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20
Q

How did JJ Thomson model the atom ?

A

as a ‘plum pudding’ - a ball of positive charge (dough), with negatively charged electrons (currants) mixed in with the ‘dough’

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21
Q

In 1909 what did Ernest Rurherford discover ?

A

that alpha particles could bounce back off atoms.

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22
Q

What did Ernest Rurherford conclude ?

A

an atom’s mass is concentrated in the atom’s centre. This was called the “nucleus” and it contained positively charged particles called protons.

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23
Q

What did Niels Bohr discover ?

A

discovered that electrons orbit (fly around) the nucleus at fixed distances

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24
Q

In 1932, what did James Chadwick discover ?

A

some particles in the nucleus have no charge at all. He called them neutrons.

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25
Q

What are the three sub-atomic particles ?

A

Proton
Electron
Neutrons

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26
Q

Where are protons found ?

A

They are found in the nucleus.

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27
Q

What is the relative charge of protons ?

A

Protons have a relative charge of +1.

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28
Q

What is the relative atomic mass of protons ?

A

1

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29
Q

An elements atomic number is what ?

A

An element’s atomic number is the number of protons it possesses.

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30
Q

All atoms of the same element have what ?

A

an identical number of protons.

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31
Q

What is the relative charge of an electron ?

A

Electrons have a relative charge of -1.

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32
Q

Where are electrons found ?

A

in fixed orbits around the nucleus.

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33
Q

In any atom the total number if negative electroms equals what ?

A

In any atom, the total number of negative electrons equals the number of positive protons, meaning atoms have no overall electric charge.

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34
Q

What is the relative atomic mass of electrons ?

A

1/2,000, which we approximate to be 0.

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35
Q

What is the relative charge of neutrons ?

A

Neutrons have a relative charge of 0 - they are neutral.

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36
Q

Where are neutrons found ?

A

Like protons, they are found in the nucleus.

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37
Q

What is the relative atomic mass of neutrons ?

A

1

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38
Q

What is the overall charge of the nucleus of an atom ?

A

Positive

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39
Q

What is an atom made up of ?

A

a positively charged nucleus surrounded by negatively charged electrons.

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40
Q

Whatnis the radius of an atom ?

A

radius of atoms is aproximately 0.1 nanometres, or 1x10-10 m.

About 5 million hydrogen atoms could fit into a pin head.

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41
Q

How many times smaller is the nucleus of an atom then the whole atom ?

A

The nucleus of an atom is 10,000 times smaller than the atom.

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42
Q

Where is Most of an atom’s mass concentrated ?

A

in the nucleus.

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43
Q

What is relative mass of an atom = to ?

A

Relative mass = number of protons + number of neutrons.

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44
Q

What is atomic number ?

A

is the number of protons in the atom

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45
Q

When looking at an atom on the periodic table how do we know the mass number and the atomic number ?

A 
Mass number (top) 
Atomic number (bottom)
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46
Q

What is the mass number and atomic number of carbon ?

A 
Mass number (top) = 12 
Atomic number (bottom) = 6
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47
Q

What is the mass number and atomic number of sodium ?

A 
Mass number (top) = 23.
Atomic number (bottom) = 11.
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48
Q

Magnesium (Mg) has an atomic number of 12. How many protons and electrons does a neutral Mg atom have?

A

12 protons and 12 electrons

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49
Q

What are isotopes ?

A

Isotopes are forms of an element that have the same number of protons, but a different number of neutrons.

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50
Q

What are hydrogens 3 isotopes ?

A

Protium
Deuterium
Tritium

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51
Q

What is protium ?

A

Protium is a hydrogen atom with 1 proton and 0 neutrons.

99.98% of hydrogen atoms are protium.

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52
Q

What is protium used for ?

A

It is used in hydrogen fuel cells and the production of plastics.

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53
Q

What is deuterium ?

A

Deuterium is a hydrogen atom with 1 proton and 1 neutron.

Around 0.02% of hydrogen atoms are deuterium.

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54
Q

What is deuterium used for ?

A

It is used in nuclear fusion

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55
Q

What is tritium ?

A

Tritium is a hydrogen atom with 1 proton and 2 neutrons.

It is very rare.

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56
Q

What is tritium used for ?

A

It is used in thermonuclear fusion weapons.

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57
Q

How many protons do hydrogen atoms contain?

A

1

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58
Q

Whats a nuclide ?

A

A nuclide is a type of isotope.

A nuclide refers to a specific nucleus that contains a certain number of protons and neutrons.

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59
Q

Fact about nuclides

A

A carbon nuclide with 6 protons and 6 neutrons is different to a carbon nuclide with 6 protons and 7 neutrons. However, both are isotopes of carbon.

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60
Q

Why do isotopes have the same properties?

A

Same number of electrons on their outer shell

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61
Q

How can we work out the realative atomic mass of chlorine ?

A

Relative atomic mass - chlorine
Chlorine can exist as 2 isotopes, 35Cl and 37Cl.
75% of chlorine is 35Cl
25% of chlorine is 37Cl
You can work out that the relative atomic mass (Ar) of chlorine is 35.5 using this information.
Ar = (0.75 x 35) + (0.25 x 37) = 35.5

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62
Q

What was rutherfords model called ?

A

Rutherford’s model was called the nuclear model

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63
Q

The relative atomic mass (Ar) is what ?

A

the average mass of all of the isotopes of an element.

It takes into account how often each isotope is found (the isotope abundance).

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64
Q

What is the equation for relative atomic mass ?

A

(Isotope abundance x isotope mass number)
——————- ——- - — ——————————
Isotope abundance

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65
Q

Calculate the relative atomic mass of uranium using these isotopic abundances (you will need a calculator to check):
238U - 50%
235U - 20%
234U - 30%

A

Remember the equation for relative atomic mass
RAM = Σ (isotope abundance x isotope mass number) / 100

Substitute the values in
RAM = (50 x 238) + (20 x 235) + (30 x 234) ÷ 100

Work out the brackets
RAM = (11,900 + 4700 + 7020) ÷ 100

Work out the answer
RAM = 236.2

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66
Q

Why is the periodic table ‘periodic’ ?

A

because elements with similar properties occur at regular intervals, i.e. periodically.

Therefore, the rows of the periodic table are called periods

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67
Q

Elements in the same column have the same number of what ?

A

Elements in the same column have the same number of electrons in their outer shell (the highest energy level).

Columns are called groups, and the group number equals the number of electrons an atom of that element has in its outer shell.

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68
Q

All elements in a column have the same number of electrons in their outer shell.
What does this mean ?

A

they have similar chemical properties.

This means they will all react in similar ways.

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69
Q

Every time you move an element to the right, what happens ?

A

the proton number increases by 1.

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70
Q

Who was john newlands ?

A

John Newlands was the first chemist to devise a periodic table.

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71
Q

How did john newlands oreder his periodic table ?

A

His periodic table was ordered by the weight of the element.

However, the table was incomplete, and some elements were placed in inappropriate groups.

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72
Q

What did Dmitri Mendeleev realise ?

A

Dmitri Mendeleev realised that there may be undiscovered elements.

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73
Q

How did Dmitri Mendeleev change Newlands table ?

A

He added gaps to Newlands’ table to account for undiscovered elements.
He even predicted the properties and masses of these undiscovered elements!

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74
Q

What discovery has shown that Mendeleev ordered elements exactly by atomic number (number of protons) ?

A

The discovery of protons and isotopes

Therefore, the modern periodic table looks very similar to Mendeleev’s (except the gaps are filled).

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75
Q

Name the 2 scientists that were key influencers of the modern periodic table?

A

John Newlands

Dimitri Mendeleev

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76
Q

What is the atomic number?

A

Number of protons in an atoms nucleus

77
Q

Where are metals found on the periodic table ?

A

Metals are found on the left of the periodic table because they have few electrons in their outer shell.

78
Q

When metals react, what happens ?

A

When metals react, they lose 1 or more of these negatively charged electrons to form positively charged ions.

79
Q

What are the properties of metals ?

A

Metals have high melting and boiling points.
Metals are good conductors of heat and electricity.
Metals are all solids (except for mercury) at room temperature.

80
Q

Where are non metals found on the periodic table ?

A

Non-metals are found on the right of the periodic table because they have many electrons in their outer shell.

81
Q

When non-metals react, what happens ?

A

Gain electrons to form negatively charged ions.

Or share electrons to form neutral molecules.

82
Q

What are the properties of non-metals ?

A

Non-metals have lower melting and boiling points than metals.
Non-metals are often found as gases.
Non-metals generally do NOT conduct heat or electricity.

83
Q

Electrons have fixed positions in atoms called what ?

A

shells or energy levels.

These shells (or energy levels) go around the atom’s nucleus

84
Q

Electrons fill an atom’s shells in order of what .

A

increasing energy

85
Q

The closer a shell is to the nucleus, the what ?

A

the lower its energy level

so the first shell that is filled is the closest to the nucleus.

86
Q

Electron configuration tells us what ?

A

Electron configuration tells us how an atom’s electrons are organised.

The inner shell (closest to the nucleus) can have a maximum of 2 electrons and the next two shells can have a maximum of 8 electrons.

Any extra electrons are then put into a fourth shell.

87
Q

Calcium atoms have 20 electrons and so whats electron configuration ?

A

2, 8, 8, 2.

88
Q

Which group of elements form DIATOMIC MOLECULES and become LESS REACTIVE as you move down the group?

A

Group 7

89
Q

What can Dot-and-cross diagrams show ?

A

electrons being transferred and ions being formed.

Dots represent electrons from 1 atom and crosses represent electrons from the other atom.

Square brackets and a charge (e.g. 2+) represent ions.

90
Q

Barium (Ba) is in group 2 and chlorine (Cl) is in group 7. In the dot-and-cross diagram for barium chloride, so how how many Barium ions and chlorine ions would there be ?

A

there would be 1 barium ion, and 2 chloride ions.

91
Q

Sodium is in group 1 and oxygen is in group 6. In the dot-and-cross diagram for sodium oxide, how many sodium ions would there be?

A

2

92
Q

When an atom gains or loses electrons, the nucleus does not change. What does this mean for the atomic mass and atomic number ?

A

This means the atomic mass and the atomic number stay the same.

93
Q

Whats a cation ?

A

Positive ion

94
Q

If an ion is positive it has fewer electrons then what ?

A

If an ion is positive, it has fewer electrons than protons.

95
Q

A 1+ charge means what ?

A 2+ charge means what ?

A

A 1+ charge means 1 less electron than proton (e.g. Na+).

A 2+ charge means 2 less electrons than protons (Ca2+).

96
Q

Whats anion ?

A

Negative ion

97
Q

If an ion is negative, it has more electrons than what ?

A

Protons

98
Q

A 1- charge means 1 what ?

A 2- charge means 2 what ?

A

A 1- charge means 1 more electron than proton (e.g. Cl-).

A 2- charge means 2 more electrons than protons (O2-).

99
Q

How many more protons than electrons does an Na+ ion have ?

A

1

100
Q

What happens in ionic bonding ?

A

In ionic bonding, a metal atom transfers electrons to a non-metal atom, allowing both of them (the metal and non-metal) to have a full outer electron shell

101
Q

Group 1 metals always lose 1 electron to form what ?

A

positive ions with a charge of +1.

E.g. a sodium atom (Na), with the electronic structure (2,8,1), loses its outer electron when forming an ion to make Na+.

102
Q

Group 2 metals always lose 2 electrons to form what ?

A

doubly positive ions.

E.g. a magnesium atom (Mg), with the electronic structure (2,8,2), loses both its outer electrons when forming an ion to make Mg2+.

103
Q

Non-metal atoms always gain electrons to form (become) what ?

A

negative ions.

E.g. a fluorine atom (F), with the electronic structure (2,7), will gain an electron when forming an ion to make F-.

104
Q

Why are noble gases unreactive ?

A

Noble gases already have a full outer shell.

Noble gases are unreactive and don’t normally form ionic bonds with other elements.

105
Q

Complete the sentence

The _____ number in the periodic table tells you the number of electrons in an atom’s outer electron shell.

A

The group number in the periodic table tells you the number of electrons in an atom’s outer electron shell.

106
Q

What are ions ?

A

Ions are particles that have a charge.

107
Q

How are ions created ?

A

Ions are created when an atom or molecule gains or loses electrons.

108
Q

Complete the sentence

Gaining electrons creates a __________ charged ion; losing electrons creates a __________ charged ion

A

Gaining electrons creates a negatively charged ion; losing electrons creates a positively charged ion

109
Q

How are positive ions created ?

A

when an atom or molecule loses electrons.

110
Q

What are positive ions often called ?

A

Cations

111
Q

What can easily lose electrons to become positively charged ions (cations) ?

A

The metals in Group 1 and 2 can easily lose electrons to become positively charged ions.

112
Q

How are negative ions created ?

A

when an atom or molecule gains electrons.

113
Q

What are negative ions called ?

A

Anions

114
Q

What are most likely to gain electrons to fill up their electron shell and become negatively charged ?

A

The non-metals in Group 7 are most likely to gain electrons to fill up their electron shell and become negatively charged.

115
Q

What are the two ways ions can be made up ?

A

1 atom (e.g. F-).

Combinations of atoms with an overall charge (e.g. SO4^2-).

116
Q

How can we predict the charge of atoms ?

A

from the periodic table based on the group number

117
Q

What is the charge of An ionic compound formula ?

A

no overall charge

118
Q

Ionic compounds made from 2 different elements end in what ?

A

-ide

119
Q

Ionic compounds made from 3 or more different elements end in what ?

A

-ate

120
Q

Potassium forms K+ and oxygen forms O2-.
We need 2 potassium ions (K+) to cancel out the 2- charge to the oxygen.

So what is the formula ?

A

Therefore, the formula becomes K2O.

121
Q

When there are multiple groups of atoms, we must use what ?

A

Brackets

122
Q

Calcium forms a Ca2+ ion, and a nitrate ion that has the formula NO3-.
We need two nitrate ions to cancel out the 2+ charge to the calcium.

Therefore, calcium nitrate has a formula of what ?

A

Ca(NO3)2.

123
Q

Calcium nitrate has the formula Ca(NO3)2. Calcium forms a Ca2+ ion. What is the charge on a nitrate ion?

A

To make calcium nitrate, we need 2 units of (NO3) for 1 unit of Ca2+.
So 1 nitrate ion must have a charge of −1 and have the formula NO3-.

124
Q

What type of structure are ionic lattices?

A

Giant structures

125
Q

How are covalent bomds formed ?

A

Covalent bonds are formed when 2 non-metal atoms share pairs of electrons.

126
Q

Why are covalent bomds strong ?

A

Covalent bonds are strong because the shared electrons are attracted to the nucleus of both atoms

127
Q

What can Covalently bonded substances be ?

A

Small molecules - water
Large molecules - polymers such as polyester and silk
Giant covalent structures - diamond

128
Q

What can be used to represent covalent bonds and show the sharing of electron pairs ?

A

Dot-and-cross diagrams

129
Q 
Each chlorine (Cl) atom begins with 7 electrons in its outer shell.
By sharing 1 pair of electrons in a single covalent bond, each Cl atom obtains what ?
A

a full outer shell with 8 electrons

130
Q

Because oxygen has 6 electrons in its outer shell, it needs to have 2 extra electrons shared with it to get a full outer electron shell.
To do this, it forms a single covalent bond with what ?

A

2 hydrogen atoms.

131
Q

Fact

A

The earlier examples show single covalent bonds (1 shared pair of electrons between atoms), but it is also possible to form double (2 shared pairs) and even triple covalent bonds (3 shared pairs).

Double and triple bonds are normally stronger and require more energy to break.

132
Q

Each oxygen needs 2 electrons to get a full outer shell.

Therefore, each oxygen atom shares 2 electrons with the other, leaving 2 pairs of electrons in the shared space between the atoms.

What is this an example of ?

A

This is an example of a double covalent bond.

133
Q

Nitrogen atoms have 5 electrons in their outer shell.

What type of bond forms between 2 nitrogen atoms?

A

Triple covalent bond

134
Q

When compared with single covalent bonds, double and triple covalent bonds…

A

Require more energy to break

Are stronger

135
Q

When nitrogen reacts with hydrogen to form ammonia, how many hydrogen atoms will bond to each nitrogen atom?

A

3

136
Q

Which diatomic element has a triple covalent bond?

A

Nitrogen

137
Q

Ionic compounds form giant structures called what ?

A

Ionic compounds form giant structures called ionic lattices

138
Q

What are ionic lattices held together by ?

A

strong electrostatic forces of attraction between positive and negative ions.

139
Q

What are the strong electrostatic forces of attraction between positive and negative ions called ?

A

These forces are called ionic bonds.

140
Q

The lattice structure of ionic compounds give them what properties ?

A

High melting and boiling points

Dont conduct electricity if solid

Conduct electricity if liquid or in solution

141
Q

Why do ionic compounds in a lattice structure have a high melting and boiling point ?

A

To break ionic bonds, significant energy is needed to overcome the electrostatic forces between the ions and electrons in the lattice.

Because of this, the melting and boiling points of ionic compounds is high.

142
Q

Why dont ionic compounds in a lattice structure conduct electricity if solid ?

A

When solid, the ions in the lattice are fixed in place.

This means that charges cannot flow, so electricity cannot be conducted.

143
Q

Why do ionic compunds in a lattice structure Conduct electricity if liquid or in solution

A

When molten, or dissolved in water, the ions in the lattice can move freely.

Because of this, charge can flow and electricity can be conducted.

144
Q

What are intramolecukar foreces ?

A

Intramolecular forces are forces within molecules.

145
Q

What are small covalent molecukes held together by ?

A

Small covalent molecules are held together by strong intramolecular forces called covalent bonds

146
Q

Lots of small covalent molecules can be held together by what ?

A

Lots of small covalent molecules can be held together by intermolecular forces

But these intermolecular forces are weak and easy to break. This means small covalent molecules have low melting and boiling points (they’re often liquids or gases at room temperature).

147
Q

How would you describe the intramolecular bonds and intermolecular forces associated with small molecules ?

A

Intramolecular covalent bonds are strong

Intermolecular forces are weak

148
Q

What does the size of a molecule affect ?

A

The size of a molecule affects the overall strength of intermolecular forces.

149
Q

What does the strength of intermolecular affect ?

A

The strength of intermolecular forces affects the properties of a molecule

150
Q

Why cant small molecules comduct electricity ?

A

Small molecules don’t contain delocalised electrons. Because of this, they cannot conduct electricity.

151
Q

Small molecules have weak intermolecular forces what does this mean ?

A

This means that they have low melting and boiling points.

Because of this, they are often liquids or gases at room temperature.

152
Q

How is Chlorine an example of a small molecule ?

A

Cl2 (the diatomic molecule of chlorine) is a small molecule with weak intermolecular forces between its molecules.

It is a gas at room temperature

153
Q

Bigger molecules attract other molecules with what ?

A

Bigger molecules attract other molecules with stronger intermolecular forces.

This means that they have higher melting and boiling points than small molecules.

154
Q

Why cant bigger molecules conduct electricity ?

A

Don’t contain delocalised electrons, and so can’t conduct electricity.

155
Q

How is Sucrose an example of a bigger molecule

A

Sucrose is made of 45 atoms and has the formula C12H22O11.

Although it is a simple molecule, its size means that its intermolecular forces are strong enough for it to be solid at room temperature.

156
Q

Why are small covalent molecules liquids or gases at room temperature?

A

When small molecules melt or boil, it’s the weak intermolecular forces that break.

Since these intermolecular forces are weak and break easily, simple covalent molecules have very low melting and boiling points.

Therefore, they exist as liquid and gases at room temperature.

157
Q

What do Some non-metals form when atoms are joined together by covalent bonds ?

A

giant covalent structures

158
Q

What are the properties of giant covalent structures ?

A

No specific formula

Very high melting point

1 large molecule

159
Q

Why dont Giant covalent structures have a specific formula ?

A

Giant covalent structures don’t have a specific formula because the structure can be any size.

160
Q

Why do giant covalent structures have a very high melting point ?

A

The strong covalent bonds between atoms make them solids at room temperature.

High temperatures and significant energy are required to break the structure’s covalent bonds

161
Q

In giant covalent structures why is there no intermolecular forces ?

A

Giant covalent structures exist as 1 large structure or molecule.

There are no intermolecular forces because there is only 1 molecule

162
Q

What are the ways of representing covalent bonds ?

A

As lines between atoms

Dot-and-cross with shells - Dots represent the outer shell electrons of atoms of 1 element.
Crosses represent the outer shell electrons of atoms of the other element.

Dot-and-cross without shells - Dots represent the outer shell electrons of atoms of 1 element.
Crosses represent the outer shell electrons of atoms of the other element.

Ball-and-stick - Balls represent atoms , Sticks represent bonds between the atoms.

163
Q

Whats a limitation of dot and cross diagrams ?

A

A limitation of this method is that it shows electrons differently for each atom, when they are actually exactly the same.

164
Q

Whats a limitation of ball and stick diagrams ?

A

A limitation of this method is that atoms are much closer together than the diagram shows.

165
Q

What are examples of 4 different types of covalent molecules ?

A

Giant covalent structures - Graphite and Diamond

Polymers - Poly(ethene) and Poly(propene)

Large covalent molecules - Long chain alkanes and Sucrose

Small covalent molecules - Oxygen and Carbon monoxide

166
Q

What is diamond an allotrope of ?

A

Diamond is an allotrope (form) of carbon

167
Q

What are the properties of diamond ?

A

High melting point

Doesnt conduct electricity

Contains covalent bonds

Very hard

168
Q

Why does diamond have such a high melting point ?

A

A lot of energy is needed to break strong covalent bonds.

Diamond has lots of strong covalent bonds. This means that it has a high melting point.

169
Q

Why doesnt diamond conduct electricity ?

A

Diamond does not conduct electricity because there are no delocalised electrons in the diamond structure.

170
Q

Each carbon atom in diamond is bonded to 4 other carbon atoms by strong covalent bonds.
What doesnthis create ?

A

This creates a giant covalent structure

171
Q

Why is diamond so hard ?

A

There are lots of strong covalent bonds in diamond. This makes it very hard.

172
Q

Because diamond is hard, what is it used for ?

A

Because diamond is hard, it is used as a cutting tool to cut other materials

173
Q

How many other carbon atoms is each carbon atom in diamond bonded to?

A

4

174
Q

What is graphite an allotrope of ?

A

Graphite is an allotrope (form) of carbon

175
Q

What are the properties of graphite ?

A

Graphite is soft

Graphite conducts electricity

Contains covalent bonds

176
Q

Why is graphite soft ?

A

The carbon atoms form layers of hexagonal (6-sided) rings, with weak intermolecular forces keeping the layers together.

The layers can easily slide over one another, so graphite is very soft.

This makes graphite useful as a lubricant and as pencil ‘lead’.

177
Q

How can graphite conduct electricity ?

A

Each carbon atom forms 3 bonds.

This means that there is 1 delocalised electron from every carbon atom.

This electron can move freely, so graphite is a good electrical conductor

178
Q

Each carbon atom in graphite is bonded to 3 other carbon atoms by strong covalent bonds.
What does this create ?

A

This creates a giant covalent structure.

179
Q

Describe the structure of graphite ?

A

Graphite is 1 of several allotropes (forms) of carbon. The weak intermolecular forces in graphite allow the layers to easily slide over one another. There is 1 delocalised electron from every carbon atom, which allows charge to flow and makes graphite a good conductor of electricity.

180
Q

What are Fullerenes ?

A

Fullerenes are molecules of carbon atoms that take up hollow structures

181
Q

What is the structure of fullerenes ?

A

Their structure is usually carbon atoms arranged in hexagonal (6-sided) rings, but pentagonal (5-sided) and heptagonal (7-sided) carbon rings can also be found.

182
Q

What was the first fullerene to be discovered ?

A

Buckminsterfullerene was the first to fullerene that was discovered

183
Q

What is the shape and formula of Buckminsterfullerene?

A

Buckminsterfullerene has a spherical shape and its formula is C60.

184
Q

Why is Buckminsterfullerene technically a simple molecule ?

A

Buckminsterfullerene is technically a simple molecule because of its fixed size.

185
Q

What are the uses of Spherical fullerenes ?

A

Generally speaking, spherical fullerenes come in a wide range of sizes, and their common uses include:

Catalysts.
Lubricants.
As vehicles for transporting drugs into our bodies.

186
Q

What are the properties of Cylindrical fullerenes ?

A

Cylindrical fullerenes - shape
Carbon nanotubes are cylindrical fullerenes.
They are often called molecular wires because they have a tiny diameter but can be incredibly long.

Conduct electricity
Strong
Small diameter

187
Q

Why are Cylindrical fullerenes so strong ?

A

Because of the strong covalent bonds between carbon atoms, nanotubes are exceptionally strong for their size

188
Q

What are the uses of Cylindrical fullerenes ?

A

The strength and electrical conductivity of nanotubes make them useful:

In electronics.
In nanotechnology.
For strengthening materials (e.g. tennis racket frames).

189
Q

The structure of fullerenes is based primarily on rings of how many carbon atoms?

A

6

GCSE Chemistry (10 decks)

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