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Chemistry > CHEMISTRY EXAM (Full GCSE) > Flashcards

CHEMISTRY EXAM (Full GCSE) Flashcards

1
Q

What elements form part in an ionic bond?

A

Metals + Non-Metals

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2
Q

What elements form part in covalent bonding?

A

Non-metals + Non-metals

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3
Q

What elements form part of metallic bonding?

A

Metals + Metals

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4
Q

What’s an ionic bond?

A

Electrostatic force of attraction:
- Strong bonds
- Soluble in water
- Can’t conduct electricity in solid, only in liquid

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5
Q

What’s a covalent bond?

A

Held together by electrostatic attraction
- A shared pair of electrons

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6
Q

What’s an allotrope of carbon?

A

Giant covalent structures out of carbon
- Same chemical properties
- Different physical properties

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7
Q

What’s a metallic bond?

A

Metal + Metal
- Complete full outer shell
- Metal ions and sea of electrons held together

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8
Q

What’re the properties of metals?

A
  • High boiling/melting points
  • Good conductors of heat/electricity
  • Malleable & Ductile
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9
Q

What’s chromatography?

A

Technique for separating components in water soluble mixtures.

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10
Q

What’s the mobile & stationary phase in chromatography?

A

Mobile: Water
Stationary: Paper

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11
Q

What’s Rf (Chromatography)?

A

Percentage (/1) of distance to solvent front

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12
Q

What’s a nanoparticle?

A

A particle with the size of 1-100 nanometres
- High surface area to volume ratio

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13
Q

When 2 elements join the end is?

A

IDE

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14
Q

When 3+ elements join & one of them is oxygen the ending is?

A

ATE

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15
Q

What’s a half equation?

A

Model for change in reactant in a reaction
- Involves charges
- Shows electron movements

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16
Q

What’s an ionic equation?

A

Symbol equation but showing changes in charge of substances
- Spectator ions are NOT involved in the reactions

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17
Q

What’s a mole?

A

Measurement for the amount of a substance
- 6.02 x 10^23 particles
- Moles = mass/Mr

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18
Q

What’s empirical formula?

A

Simplification of molecular formula

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19
Q

What’s an exothermic reaction?

A

Reaction that takes in less energy than it gives out.

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20
Q

What’s an endothermic reaction?

A

A reaction that takes in more energy than it gives out.

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21
Q

What’s a reaction profile?

A

Model for energy in a reaction
- Activation Energy: Energy needed to start a reaction

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22
Q

How do you calculate energy change?

A
  • Count the number of bonds
  • Multiple by their energy
  • Then EA = endothermic-exothermic
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23
Q

What’s a redox reaction?

A

Reactions where oxidation and reduction take place.

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24
Q

What’s oxidation & oxidizing agent?

A

Oxidation: Gain of oxygen or loss of electrons
Oxidising Agent: Substance that removes electrons from other substances

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25
Q

What’s reduction and reducing agents?

A

Reduction: Removal of oxygen or gain of electrons
Reducing Agent: Substance that can give electrons to other substances

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26
Q

What’s an acid?

A

Contain hydrogen in formulae, substance which releases Hydrogen ions when dissolved in water.

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27
Q

What’s a base?

A
  • Opposite to acids
  • Contain elements that react with acids to make water
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28
Q

What’s an alkali?

A

Bases that make OH- ions
- Neutralisation with acids

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29
Q

Neutralisation word equation?

A

Acid + Alkali –> Salt + water

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30
Q

Acid carbonate reaction word equation?

A

Acid + Carbonate –> Salt + water + carbon dioxide

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31
Q

Metal acid reaction word equation?

A

Metal + Acid –> Salt + Hydrogen

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32
Q

Strong/weak acids classification?

A

Classification of acids depend on how much they ionise the water

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33
Q

What’s a dilute acid?

A

Contains low ratio of acid to solution

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34
Q

What’s a concentrated acid?

A

Contain high ratio of acid to solution

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35
Q

What’s electrolysis?

A

Splitting up substances with electricity

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36
Q

What happens at the Anode?

A

Anode (+):
- Attracts negative ions
- Lose electrons to become atoms

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37
Q

What happens at the Cathode?

A

Cathode (-):
- Attracts positive ions (metals)
- Gains electrons to become atoms

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38
Q

Rules for anode:

A
  • If ions are halides, then the halogen is produced
  • If ions aren’t halides, then oxygen is produced
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39
Q

Rules for cathode:

A
  • If metal ions are more reactive than hydrogen, then hydrogen is produced
  • If metal ions are less reactive than hydrogen, then the metal is produced
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40
Q

What’s electroplating?

A
  • Technique where object is coated with a metal
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41
Q

How does electroplating work?

A
  • Coating metal is an anode and electrolyte containing coating metal
  • Coating metal gets separated and attracted to object (cathode) where it coats the object
  • Coating metal (anode), loses electrons and ions dissolve in solution
  • Can also be used to purify copper (with a sample of pure copper)
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42
Q

What’s an isotope?

A

Different forms of the same element:
- Same number of protons
- Different number of neutrons

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43
Q

What’re simple molecules?

A

Molecules with covalent bonds
- Low melting/boiling points
- Covalent bonds are strong
- Bonds between molecules are weak
- Don’t conduct electricty

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44
Q

What’s a polymer?

A

Lots of molecules (monomers join together).
- This is polymerisation (needs high pressure and catalyst)
- Plastics are polymers

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45
Q

What’s an alloy, why is it used?

A
  • Mixing metals with other elements make alloys
  • Used to change its properties
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46
Q

What does pure mean?

A
  • Made up of a single element
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47
Q

How does simple distillation work?

A
  • Separates liquids from solutions
  • Can only be used to separate things with very different boiling points
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48
Q

What’s fractional distillation?

A
  • Used to separate mixture of liquids
  • Uses different boiling points to seperate liquids
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49
Q

What’s filtration?

A

Filtration is used to separate an insoluble solid from a liquid
- Uses filter paper, and only water can get through

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50
Q

What’s crystallization?

A

Separates soluble solids from a solution

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51
Q

What’s the solvent?

A

Substance that dissolves a solute

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52
Q

What’s a solute?

A

Substance that dissolves in a solvent, forming a solution?

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53
Q

What’re the different state symbols?

A

(s): Solid
(l): Liquid
(g): Gas
(aq): Aqueous

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54
Q

What’re alkali metals?

A

Group 1:-
- Low melting/boiling points
- High density

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55
Q

How does reactivity change in alkali metals?

A

Gets more reactive as you go down the group.
- As it’s further away and you need to lose it
- so less energy is needed to to remove it

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56
Q

What’re halogens?

A

Group 7:
- Diatomic
- As you go downt he group, melting/boiling points increase

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57
Q

How does reactivity change going down halogens?

A

As you go down the group, the reactivity decreases.
- This is because it needs to gain an electron
- And further down it has more shells
- So more energy is needed to gain the electron as it’s further from nucleus

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58
Q

What’re noble gases?

A
  • Very unreactive (full outer shells)
  • Colourless
  • Monatomic
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59
Q

What’re transition metals?

A

Metals in the middle of periodic table:
- Good conductors of heat/electricity
- High density, melting points, malleability & ductility
- Harder but less reactive than alkali metals
- Reactive decreases from left to right

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60
Q

How can you test for carbon dioxide?

A
  • Bubbling it through limewater
  • Will turn cloudly
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61
Q

How do you test for hydrogen?

A

Squeaky Pop Test:
- Makes a pop with a lighted splint

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62
Q

How can you test for oxygen?

A
  • Glowing splint
  • Will light if there’s oxygen
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63
Q

How can you test for chlorine?

A

Use litmus paper
- If gas is chlorine, it will bleach litmus paper

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64
Q

How do you draw covalent bonds?

A
  • Dots & Crosses diagrams
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65
Q

What’s an ion?

A

An ion is a charged particle or molecule due to a gain or loss of an electron.

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66
Q

First three shells?

A

2,8,8

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67
Q

Wha’re polymers?

A

Long chain molecules (monomers).

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68
Q

What’s polymerization?

A

The formation of polymers with high pressure & catalyst.

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69
Q

Force strength of intermolecular forces?

A

Weak.

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70
Q

Force strength of covalent bonds?

A

Strong.

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71
Q

Force strength of ionic bonds?

A

Strong.

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72
Q

What causes strong metallic bonding?

A

Strong attraction between delocalized electrons & positive ions.

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73
Q

what did the gold foil experiment show?

A

Some alpha particles were deflected, and a small percentage bounced back.

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74
Q

What did the gold foil experiment prove?

A

That the atom was mostly empty.
With a positive nucleus.

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75
Q

What’re giant covalent structures?

A

Lots of covalent bonds hold atoms together.

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76
Q

Properties of giant covalent structures?

A
  • High melting points
  • Can’t conduct electricity
  • Strong bonds
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77
Q

Examples of giant covalent structures?

A
  • Diamond
  • Graphite & Graphene
  • Fullerenes
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78
Q

Why do ionic compounds only conduct electricity when molten?

A

Because when it’s solid, ions can’t move.
But when molten, ions can move and carry an electrical current.

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79
Q

Why do simple molecules not conduct electricity?

A

Because there aren’t any free electrons or ions.

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80
Q

Why do simple molecules have low melting/boiling points?

A

Atoms have strong covalent forces.
But the forces that hold the molecules together are very weak, so it takes low energy to break them.

81
Q

Carbonate ion charge?

A

2-

82
Q

Sulfate ion charge?

A

2-

83
Q

Hydroxide ion charge?

A

1-

84
Q

Oxide ion charge?

A

2-

85
Q

Nitrate ion charge?

A

1-

86
Q

What’s ammonia?

A

NH3

87
Q

What’s a symbol equation?

A

Equation that shows symbols of reactants and products, with the amount of each thing.

88
Q

What’re state symbols?

A

Tell you the state of a substance in an equation?

89
Q

What’re half equations?

A

Show how electrons are transferred during reactions.

90
Q

When can you use half equations?

A

Only in redox reactions.

91
Q

What’s a mole number?

A

6.022 x 10^23

92
Q

Moles equation?

A

Moles = Mass / Mr

93
Q

What’s exothermic & endothermic?

A

Exothermic: Gives out more energy than it takes in.

Endothermic: Takes in more energy than it gives out.

94
Q

What’s a reaction profile?

A

Graph that shows energy levels of the reactants & products in a reaction.

95
Q

What’s activation energy?

A

Minimum amnount of energy needed for bonds to break and start a reaction?

96
Q

Breaking bonds takes in or gives out energy?

A

Takes in energy

97
Q

Forming bonds takes in or gives out energy?

A

Gives out energy

98
Q

Bond Energy Change equation?

A

Overall Energy Change = Energy to break bonds - Energy released by forming bonds

99
Q

Acid + Metal –> ?

A

Acid + Metal —> Salt + Hydrogen

100
Q

Acid + Metal Carbonate –> ?

A

Acid + Metal Carbonate —> Salt + Water + Carbon dioxide

101
Q

Acid + Alkali –> ?

A

Acid + Alkali –> Salt + Water

102
Q

How does electrolysis work?

A

1) Current decomposes electrolyte
2) Cations (+) & Anions (-) go to Cathode & Anode respectively.
3) Cations (+) gain electrons (reduction)
4) Anions (-) lose electrons (oxidation)
5) This makes substances become uncharged

103
Q

What does molten ionic produce in electrodes?

A

Cathode (-): Metal atoms
Anode (+): Negative ions become atoms.

104
Q

What does aqueous solutions produce in electrodes?

A

Cathode: If metal more reactive than H than H is produced. Otherwise the metal is produced.

Anode: If Halide ions are present the halogen is produced, otherwise oxygen is produced.

105
Q

How can you measure pH of a solution?

A
  • Indicator
  • pH probe
106
Q

What’re 3 properties of ceramics?

A
  • Insoluble
  • Very Strong
  • Do not react chemically
  • Very brittle
  • Easily moulded
107
Q

What are group 1 elements?

A

Alkali metals

108
Q

What do halogens react vigorously with?

A

Alkali metals

109
Q

What is a halogen displacement reaction?

A

When halogens react with halides and the halogen displaces the less reactive halogen from the halide.

110
Q

How do noble gases change going down the group?

A
  • Boiling point increases as attractive forces between atoms gets stronger
  • Density increases
111
Q

What groups do transition metals occupy?

A

Groups 3-12

112
Q

Word equation for Metal + water?

A

Metal + Water –> Metal hydroxide + Hydrogen

113
Q

What’s a metal displacement reaction?

A

A more reactive metal displaces a less reactive metal from a solution.

114
Q

What’s more reactive than carbon?

A

Lithium, Potassium, Barium, Calcium, Sodium, Magnesium & Aluminium

115
Q

What’s less reactive than carbon but more reactive than hydrogen?

A

Zinc, Iron, Nickel, Tin & Lead

116
Q

What’s less reactive than hydrogen?

A

Copper, Mercury, Silver, Gold & Platinum

117
Q

How can you test for hydrogen?

A

Place a lighted splint in container, if it’s hydrogen it will ignite with a squeaky pop.

118
Q

What is the flame test?

A

Heating metal ions produce a different colour depending on the ion.

119
Q

What colour do lithium, sodium, potassium, calcium & copper turn in flame test?

A

Lithium (Li+): red
Sodium (Na+): yellow
Potassium (K+): lilac
Calcium: (Ca2+): orange-red
Copper (CU2+): green-blue

120
Q

What colour of hydroxide precipitate do iron (ii), iron (iii), coper (ii), calcium & zinc produce?

A

Fe2+: green
Fe3+: orange-brown
Cu2+: blue
Ca2+: white
Zn2+: white

121
Q

What’s instrumental method of analysis?

A

Uses machines to analyse substances.

122
Q

Benefits of instrumental methods of analysis?

A
  • Sensitivity
  • Accuracy
  • Speed
123
Q

What’s the yield of the product?

A

Mass of the product made in a chemical process.

124
Q

What’s the theoretical yield?

A

Maximum mass possible from a given mass of reactants.

125
Q

How do you calculate theoretical yield?

A
  • Calculate moles of limiting reactant (mass/Mr).
  • Figure out moles of product through ratio
  • Multiply by Mr of product and you get mass in grams
126
Q

Percentage yield equation

A

percentage yield = (actual yield)/(theoretical yield) x 100

127
Q

Why is percentage yield never 100%?

A
  • Reactants might react with other substances to make new products
  • Reaction might not be complete
  • May loose product when you separate or collect it
  • Reactants might not be pure
128
Q

What’s atom economy?

A

Percentage of the product you want over the total mass (Mr) of products.

129
Q

Atom economy equation?

A

Atom economy = (useful product)/(total mass of products) x 100

130
Q

What’s a reaction pathway?

A

Reactions undertaken to make a particular substance.

131
Q

What must be considered when deciding a reaction pathway?

A
  • yield of product
  • atom economy
  • usefulness of by-products
  • rate of reaction
132
Q

What’s a litre equal to?

A

1 cubic decimetre (dm3)

133
Q

Concentration equation mass

A

Concentration (g/dm3) = mass (g) / volume (dm3)

134
Q

Concentration equation moles

A

Concentration (mol/dm3) = moles / volume (dm3)

135
Q

What’s a titration?

A

Titration is a technique used to find the concentration of an acid or alkali through neutralization reaction.

136
Q

Hoes does titrations work?

A
  • Add a known volume of alkali to conical flask
  • Then add acid from burette
  • When it changes colour (indicator), reaction completed, neutralization
  • Calculate titre
137
Q

What’s a titre?

A

Volume of acid added to the alkali in the flask

138
Q

How much volume does 1 mol of gas occupy at room temp & pressure (RTP)?

A

24dm3

139
Q

What’s the molar volume?

A

Volume one mol of a gas occupies at RTP

140
Q

How to calculate volume at RTP?

A

Volume = moles x 24dm3/mol

141
Q

What’s rate of reaction?

A

How quickly reactants are used up, or products are formed.

142
Q

What increases rate of reaction?

A
  • Temperature
  • Concentration
  • Pressure
  • Surface area
  • Catalysts
143
Q

What are reversible reactions?

A

Reaction goes both ways:
Reactants <–> Products

144
Q

What is hydrated?

A

Contains water molecules

145
Q

What is anhydrous?

A

Doesn’t contain water molecules

146
Q

What’s the reversible reaction symbol?

A

⇌

147
Q

What is dynamic equilibrium?

A

In a closed system, the reversible reactions moves both ways at the same rate.

148
Q

What happens at dynamic equilibrium?

A
  • Forward & Backward reaction will still happen, but at the same rate
  • Concentrations of reacting substances are constant
149
Q

What’s the equilibrium position?

A

Ratio of concentration of products to reactants?

150
Q

What does it mean if the equilibrium position is to one side?

A

It means that one side has a higher concentration.
For example: left side means reactants have a higher concentration.

151
Q

What happens when you increase the pressure in a reversible reaction?

A
  • Equilibrium position moves to the side with least moles
  • Reaction to side with least moles is favoured
152
Q

What happens when you increase the concentration in a reversible reaction?

A
  • Equilibrium position moves to the side with least concentration
  • Reaction to side with least concentration is favoured
153
Q

What happens if you increase the temperature in a reversible reaction?

A
  • Endothermic reaction is favoured
154
Q

What’s equilibrium yield?

A

Amount of desired product present in a reaction at equilibrium.

155
Q

What are the compromises in temperature in reversible reactions?

A
  • Temp might need to be low for high yield
  • But at low temp, ROR is slow
  • Compromise temp is used to balance
156
Q

What are the compromises in pressure in reversible reactions?

A
  • Pressure might need to be high for high yield
  • But at high pressures, it’s expensive, requires lots of energy and tough vessels
  • Compromise pressure is used to balance
157
Q

What elements do plants need?

A

Nitrogen, phosphorus & potassium.

158
Q

What do fertilizers do?

A

They replace the elements used by plants as they grow.

159
Q

What’s the Haber process?

A

Produces ammonia from nitrogen and hydrogen.

160
Q

Haber process equation

A

N2 + 3H2 ⇌ 2NH3

161
Q

How are reactants produced in the Haber process?

A

Nitrogen: Fractional distillation of liquefied air
Hydrogen: Reacting natural gas with steam

162
Q

What are the condition of the Haber process?

A
  • Iron catalyst
  • High temperature (450ºC)
  • High pressure (200atm)
163
Q

What’re the different industrial processs?

A
  • Batch
  • Continous
164
Q

What’re the difference between batch & continuous processes?

A

Batch: Make a small amount at a time
Continous: Large amounts and go all the time

165
Q

How is ammonia collected during the Haber processes?

A
  • Gases in reaction vessel cooled, liquid ammonia collected.
  • Nitrogen & Hydrogen recycled to continue making ammonia
166
Q

What’s the contact process?

A

Process for making Sulfuric acid (for fertilizers) from sulfur, air & water.

167
Q

What’s the first step? (Contact process)

A

Sulfur burn in air to produce sulfur dioxide

S + O2 –> SO2

168
Q

What’s the second step? (Contact process)

A

Sulfur dioxide & oxygen react to produce sulfur trioxide

2SO2 + O2 ⇌ 2SO3

169
Q

What’s the third step? (Contact process)

A

Sulfur trioxide reacts with water to make sulfuric acid.

H2O + SO3 –> H2SO4

170
Q

What’re two ways of making ethanol?

A
  • Fermentation
  • Hydration of ethene
171
Q

What’s an ore?

A

rock or mineral that contains extractable metal.

172
Q

What’s malachite?

A

copper carbonate

173
Q

What’s bauxite?

A

aluminium oxide

174
Q

What’s hematite?

A

iron(III) oxide

175
Q

How are metals extracted from ores?

A

More reactive than Carbon: Electrolysis
Less reactive than Carbon: Heating compounds with carbon

176
Q

How can copper be extracted?

A

Stage 1: Roasted in air
2CuS + 3O2 –> 2CuO + 2SO2

Stage 2: Heated with carbon
2CuO + C –> 2Cu + CO2

177
Q

How is iron extracted from its ore?

A

Using a blast furnace.

178
Q

What’s Stage 1? (Blast furnace)

A

Coke burns in hot air

C + O2 –> CO2

179
Q

What’s Stage 2? (Blast furnace)

A

Coke is added to CO2, making CO
C + CO2 –> 2CO

180
Q

What’s Stage 3? (Blast furnace)

A

Carbon monoxide reduces iron oxide to produce iron

3CO + Fe2O3 –> 3CO2 + 2Fe

181
Q

How is aluminium oxide electrolysed?

A
  • Dissolved in cryolite to lower melting point
  • Electrolysed at 950ºC
  • Aluminium produced at the cathode
182
Q

Why must the anodes be replaced when aluminium is electrolysed?

A

Because, oxygen (from Aluminium oxide) reacts with the anodes making CO2, deteriorating the anode.

183
Q

What is bioleaching?

A

Bacteria which oxidise metal ions, to produce low grade ores.

184
Q

What is phytoextraction?

A

Plants absorb metal ions, then they are burned and a high-grade ore ash is produced.

185
Q

What are the benefits of bioleaching and phytoextraction? And drawbacks?

A

They are cheaper, produce less waste and use less energy.

But they are slow.

186
Q

What’s an alloy?

A

Mixture of two or more elements (one is a metal.

187
Q

Examples of alloys?

A
  • Solder
  • Brass
  • Bronze
188
Q

What is corrosion?

A

Reaction of a metal with substances in its surroundings.

189
Q

What is rusting?

A

A type of corrosion when iron and steel react with water or oxygen.

190
Q

Rusting of iron equation

A

iron + oxygen + water –> hydrated iron(III) oxide

191
Q

How can you reduce rusting?

A
  • Painting
  • Coating with oil, grease, plastic
  • Plating with zinc or tin
192
Q

What is sacrificial protection?

A

Protecting iron/steel from corroding with a more reactive metal that corrodes first.

193
Q

What is galvanizing?

A

Dipping object in molten zinc. This stops air/water eaching object and also acts as a protective layer.

194
Q

What are composite materials?

A

Combination of 2+ materials with different properties. Composite material has different properties.

195
Q

What’s a life-cycle assessment?

A

A ‘cradle-to-grave- analysis of making, using and disposing of a product.

196
Q

What does a life-cycle assessment look at?

A

Cradle: Materials and energy used in manufacturing

Use: energy, water and substances used during utilisation

Grave: energy and space needed to dispose the product

197
Q

Why is recycling good?

A
  • Conserves limited raw materials
  • Reduces waste
  • Reduces energy usage
  • Reduces release of harmful substances
198
Q

What happens during processing in recycling?

A
  • Metals are heated, and poured into moulds making ingots.
  • Paper is mixed with water, cleaned and made new paper
  • Glass and some polymers are heated and moulded into new objects

Chemistry (8 decks)

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