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1
Q

Name two tests for water :

A
Anhydrous copper(II) sulfate 
Anhydrous cobalt (II) chloride
2
Q

Colour changes of anhydrous copper (II) sulfate ?

A

White solid to blue

3
Q

Anhydrous cobalt (II) chloride colour changes:

A

Pale blue to pink

4
Q

What is hard water ?

A

Water that doesn’t readily form a lather with soap

5
Q

What is soft water

A

Water that readily forms a lather with soap

6
Q

What is hardness in water caused by ?

A

Ca2+ or Mg2+ ions

7
Q

What is the chemical name for soap ?

A

Sodium Stearate

8
Q

What does boiling do?

A

Removes temporary hardness

9
Q

What is temporary hardness caused by ?

A

Dissolved calcium hydrogen carbonate

10
Q

Formula for temporary hardness arising in water

A

CaCO3 + H2O + CO2 -> Ca(HCO3)2

11
Q

How does temporary hardness arise in water?

A

Limestone reacts with rainwater containing dissolved carbon dioxide to form calcium hydrogen carbonate solution

12
Q

Equation for boiling

A

Ca(HCO3)2 (aq) -> CaCO3(s) + CO2(g) + H2O(l)

13
Q

What does an ion exchanger do ?

A

Removes both perm. And temp.

Dissolved Ca2+ ions in hard water are removed and replaced by Na2+ ions from the ion exchange resin

14
Q

What is the chemical name for washing soda

A

Hydrated sodium carbonate

15
Q

What does washing soda do?

A

Removes both temp. And perm.
Dissolved calcium or magnesium ions are removed due to a reaction with carbonate ions from the washing soda t form insoluble calcium carbonate or magnesium carbonate

16
Q

Advantages and disadvantages ir hard water

A

Hard water tastes better
It’s good for health teeth and bones
But
It produces a scum with soap (wastes soap)

17
Q

What does desiccant mean

A

Drying agent

18
Q

Anhydrous calcium chloride

A

White solid absorbs water from the air until eventually a colourless solution forms

19
Q

Self-indicating Silica gel colour changes

A

Blue to pink

20
Q

Normal silica gel colour changes

A

White and remains white when it absorbs moisture from the air

21
Q

What does hygroscopic mean

A

Absorbs moisture from the air

22
Q

Why is fluoride added to drinking water ?

A

It prevents tooth decay

23
Q

Why do some people not like fluoride being added to drinking water ?

A

It can cause stomach cancer

24
Q

What is barium sulfate used for?

A

Patients with stomach intestinal problems to X-ray the stomach or bowel

25
Q

Why is barium sulfate safe to use ?

A

It has a low solubility in water so it cannot act as a poison in the body

26
Q

What does exothermic mean ?

A

Gives out heat

27
Q

What does endothermic mean ?

A

Takes in heat

28
Q

What do all chemicals possess ?

A

Internal energy- energy is required to break all types of bonds

29
Q

What is bond breaking ?

A

Endothermic

30
Q

What is bond makeing ?

A

Exothermic

31
Q

What is thermal decomposition ?

A

A substance breaks down when heated

32
Q

What is the general equation for thermal decomposition ?

A

Metal carbonate -> metal oxide + carbon dioxide

33
Q

What are the most common examples used in thermal decomposition ?

A

Copper (II) carbonate

Calcium carbonate

34
Q

What colour is copper carbonate ?

A

Green solid

35
Q

Colour changes of copper carbonate when heated ?

A

Green to black solid= copper oxide, co2 released

36
Q

What colour is calcium carbonate ?

A

White solid

37
Q

What is calcium carbonate used for ?

A

To remove acidic impurities from the iron ore in the blast furnace

38
Q

What happens when CaCO3 is heated ?

A

It glows orange and co2 gas is release

39
Q

What happens in a line kiln?

A

Limestone (CaCO3) is decomposed into lime (calcium oxide)

40
Q

Process in lime kiln ?

A

Hot air is blown into lime kiln to burn coke and heat calcium carbonate until it decomposes,

41
Q

What is calcium carbonate used for ?

A

Agriculture- neutralise the acidity in soil water. Also used as an antacid in stomach to reduce excess stomach acidity

42
Q

Mining limestone advantages and disadvantages??

A

It provides employment, provided better transport links
But
It creates an eyesore and causes dust pollution

43
Q

What is the atmosphere?

A

The collection of gases that surrounds the earth

44
Q

What is air ?

A

The atmosphere near the surface

45
Q

Percentages of air in atmosphere?

A

79% nitrogen , 20% oxygen, 1% argon, 0.03% water vapour and carbon dioxide

46
Q

What is today’s atmosphere ?

A

An oxidising one

47
Q

What causes changes in the atmosphere?

A

Photosynthesis
Carbonate rocks being formed
Fossil fuels being formed over time

48
Q

What theory did Alfred wegener propose ?

A

Continental drift in 1912

49
Q

What is continental drift?

A

The con indie BT’s on the surface of the earth are moving and that th y were one single land mass millions of years ago- since then th have drifted away from each other

50
Q

Examples to back up continental drift theory.?

A

Shape of continents - South America would fit exactly into Africa
Fossil fuels found in continents that he proposed were once joined were very similar
Similar species of animals

51
Q

Why do tectonic plates move ?

A

Due to the convection currents in the liquid mantle

52
Q

Describe what happens when plates collide directly with each other ?

A

Mountain ranges can be formed

53
Q

What happens when plates are pulled apart from each other ?

A

Formation of volcanoes - liquid part of the mantle l reaches the earths surface- - lava

54
Q

What happens when plates try to move past each other ?

A

Earthquakes

55
Q

What is a redox reaction?

A

One where oxidation and reduction both occur simultaneously

56
Q

What is oxidation?

A

Gain of oxygen
Loss of electrons
Loss of hydrogen
OILRIG- Electrons

57
Q

What is reduction ?

A

The gain of hydrogen
Loss of oxygen
Gain of electrons
OILRIG- electrons

58
Q

What is the chemical name for rust ?

A

Hydrated iron(III) oxide

59
Q

What two conditions are required for rusting ?

A

Moisture( water) air (oxygen)

60
Q

Example of an investigation to fine out the factors of rusting ?

A

Three test tubes - one with ion nail and water only
Second with ion nail, boiled water and layer of olive oil
Third with suspended iron nail and anhydrous calcium chloride

61
Q

How to prevent rusting ?

A
  1. Painting
  2. Alloying
  3. sacrificial protection
62
Q

What can be painted onto the metal to prevent rusting ?

A
  1. Paint - cars bridges etc
  2. Oil or grease- tools and machinery
  3. Plastic coating - cover bicycle handlebars
  4. Plating with another metal e.g tin -making cans for food or chromium- vehicle bumpers ( bother are applied to steel by electrolysis
63
Q

What is sacrificial protection?

A

Bars of magnesium can be added to ships etc to prevent rusting. The magnesium corrodes instead of he iron or steel but must be replaced with fresh magnesium periodically

64
Q

What is galvanising ?

A

Iron can be coated in zinc , zinc oxidises to form a layer of zinc oxide

65
Q

What is alloying ?

A

Allot is a mixture of two or more elements , at least one of which is a metal

66
Q

Combustion of carbon?

A

C + O2 -> CO2

67
Q

Incomplete combustion of carbon ?

A

2C + O2 -> 2CO

68
Q

What happens when magnesium is burned with oxygen ?

A

Grey metal to a bright white light releasing heat and forming a white powder

69
Q

Observations of sulfur with oxygen ?

A

Yellow powder melts to a red liquid and burns with a blue flame releasing heat and forming a colourless pungent gas called sulfur dioxide

70
Q

What gas is used to reduce metal oxides e.g copper(II) oxide ?

A

Hydrogen

71
Q

Observations of copper 2 oxide being reduced ?

A

Black copper oxide changes to a pink colour and condensation is present in the tube

72
Q

Why is excess hydrogen burnt when reducing copper oxide ?

A

To prevent flammable hydrogen gas bulking up in the laboratory

73
Q

What four things does the rate of a reaction depend on. ?

A

Surface area of solid particles
Concentration
Temperature
Catalyst

74
Q

What reactions are used in rate of reaction experiments?

A
  1. Metal reacting with a dilute acid- produces hydrogen gas
  2. Marble chips reacting with HCL produces water and carbon dioxide
  3. Catalytic decomposition of hydrogen peroxide- produces oxygen
75
Q

What is effervescence ?

A

Bubbling

76
Q

What does cotton wool do when measuring a change in mass ?

A

Stops any liquid loss from the flask

77
Q

Method of measuring a change in mass ?

A
  1. 1g of large marble chips in a conical flask and HCL with cotton wool at the top on top of an electronic balance
  2. Then repeat with 1g of smaller marble chips
  3. Plot a graph showing the results
78
Q

Measuring gas volume ?

A

Collect the gas in a gas syringe

79
Q

What apparatus is needed for measuring gas volume ?

A
Thistle funnel 
Delivery tube
Conical flask 
Bung 
Gas syringe 
HCL 
Marble chips
80
Q

Formula for rAte?

A

Rate= 1/time

81
Q

What are the units of rate v?

A

S-1

82
Q

What is activation energy ?

A

The minimum energ that the colliding particles need to react l

83
Q

Why does a higher temperature speed up the rate of a reaction ?

A

The particles have more energy and move faster
This leads to more collisions
More successful collisions in a given period of time- activation energy can be overcome
Increases rate of reaction

84
Q

How does having a higher concentration of a solution increase the rate of a reaction ?

A

There are more particles present in the same volume
This leads to more collisions between the particles
More successful collisions in a given period of time
Increases the rate of the reaction

85
Q

Tips for graphs that have a higher temp?

A

Gas volume starts at zero
Gas volume gets higher every time
The line levels off earlier
Line ends at same final gas volume

86
Q

What is a catalyst?

A

A substance that speeds up the rate of a reaction without being used up itself

87
Q

How do catalysts work?

A

They lower the activation energy when ch increases the number of successful collisions in a given period of time

88
Q

What catalyst is used in the decomposition of hydrogen peroxide ?

A

Manganese (IV) oxide

89
Q

What catalyst is used in the contact process ? (Sulfuric acid )

A

Vanadium (V) oxide

90
Q

What catalyst is used in the haben process ? ( ammonia )

A

Iron

91
Q

What do manufacturers want to achieve the maximum of ?

A

Yield

92
Q

Why might manufacturers prefer getting a lower yield ?

A

Factors can be expensive

93
Q

Why might high pressure for gases not be used ?

A

It is expensive and can be dangerous for staff

94
Q

What is a compromise temperature ?

A

Allows enough of the product to be made in as short time period as possible

95
Q

Why might using s better catalyst be more effective and sustainable ?

A
  1. Using less energy - reduces the temperature and pressure required
  2. Using renewable raw material
  3. Being carried out in fewer steps - saves waste
96
Q

How do you collect indelible gases ?

A

Collection over water - trough , beehive shelf , gas jar, delivery tube

97
Q

How do you collect soluble gases ?

A

Downward or upward delivery

98
Q

When do you use downward delivery ?

A

Soluble gas , denser than air

99
Q

When do you use upward delivery ?

A

Soluble gas, less dense than air

100
Q

What is hydrogen?

A

Colourless odourless gas, - collection over water

101
Q

Observations of hydrogen gas with air?

A

Clean blue flame , producing water vapour

102
Q

What is the equation for the haben process ?

A

N2 + 3H2 2NH3

103
Q

What do you use to prepar hydrogen ?

A

Zinc of magnesium and HCL

104
Q

What is a test for hydrogen ?

A

Lit splint , squeaky pop

105
Q

What is hydrogen used for ?

A

Rocket engines
Clean fuel
Weather balloons

106
Q

Why is hydrogen described as a clean fuel ?

A

Because the only product of combustion is non-polluting

107
Q

What is charcoal ?

A

An impure form of carbon which is a black solid

108
Q

Observations of combustion of carbon ?

A

Orange flame forming a colourless odourless gas called carbon dioxide

109
Q

How is carbon dioxide prepared ?

A

From calcium carbonate and HCL

110
Q

How is carbon dioxide collected ?

A

Over water

111
Q

Physical properties of carbon dioxide ?

A

Colourless odourless gas

112
Q

What does carbonic acid do ? And how is it formed ?

A

Causes the acidity in dizzy drinks

Carbon dioxide reacts with water to form the weak acid- carbonic acid

113
Q

Observations of carbon dioxide and magnesium?

A

Bright white light, white solid produced and there are black specks (carbon)

114
Q

What is a test for carbon dioxide ?

A

Bubble gas through limewater

The colourless solution becomes milky

115
Q

What is carbon dioxide used for ?

A

In fire extinguishers

Dry ice

116
Q

What is nitrogen ?

A

Colourless and odourless gas

117
Q

How do you collect nitrogen ?

A

Collection over water

118
Q

Why is nitrogen unreactive ?

A

Because of the triple covalent bond between the nitrogen atoms in N2 molecules. The triple covalent bond requires substantial energy to break before the nitrogen atoms can react

119
Q

How do you prepare nitrogen ?

A

Removing carbon dioxide oxygen and water vapour from s sample

120
Q

What is the haber process ?

A

450 degrees Celsius
Pressure of 200atm
Iron catalyst
The double arrow represents a reversible reaction

121
Q

What is nitrogen used for ?

A

Foot packaging

Liquid- coolant

122
Q

What is ammonia ?

A

A colour less pungent gas

123
Q

How is ammonia collected ?

A

Upward delivery

124
Q

Test for ammonia ?

A

Dip a glass rod in HCL and put this in a sample of gas

White smoke of ammonium chloride produced of ammonia is present

125
Q

Nitrogenous fertilisers ?

A

Excessive us of nitrogenous fertilisers on soil leads to leaching if nitratesbinto soil water and finally into river waters. This leads to eutrophication

126
Q

What can increased levels of nitrates do ?

A

Lead to stomach cancer and also blue baby syndrome

127
Q

What is eutrophication?

A

Nitrogenous fertilisers in rivers and lakes leads to excess algae growth
This leads to death of algae
Decomposing microorganism use up oxygen gas in the water breaking down dead algae
This leads to a lack of oxygen and the death of fish

128
Q

Observations of Aqueous ammonia and copper ions?

A

Pale blue precipitate of copper hydroxide

Excess- redissolves to form a dark blue solution

129
Q

Aqueous ammonia with iron (II) ions ?

A

Pale green precipitate of iron hydroxide

Excess-doesn’t tedussolve

130
Q

Aqueous ammonia and iron(III) ions ?

A

Red brown precipitate

Excess- doesn’t redissolve

131
Q

Aluminium and aqueous ammonia ?

A

White precipitate

Excess- doesn’t resissolve

132
Q

Aqueous ammonia and zinc ions ?

A

White precipitate

Excess - redissolve stop form colourless solution

133
Q

Aqueous ammonia and magnesium ?

A

White precipitate

Excess- doesn’t redissolve

134
Q

What is oxygen ?

A

Colourless odourless gas

135
Q

How is oxygen collected ?

A

Collection over water ?

136
Q

How is oxygen prepared ?

A

Hydrogen peroxide and manganese (IV) oxide

137
Q

Test for oxygen ?

A

Apply a glowing splint and the glowing splint will relight

138
Q

What is oxygen used for ?

A

Welding
Medicine
Rocket engines

139
Q

Oxygen and hydrogen v?

A

Clean blue flame pro slicing a colourless odourless gas that condenses to form a colourless liquid ( water)

140
Q

Oxygen and carbon ??

A

Black solid burns with and orange sooty flame forming a colourless gas (co2 )

141
Q

Oxygen and sulfur ?

A

Yellow solid sulfur melts to a red liquid and burns with a clue flame giving a colourless pungent gas (SO2 )

142
Q

Oxygen with zinc ?

A

Grey cooks glows red on heating producing a yellow solid which changes to a white solid on cooling zinc oxide

143
Q

Oxygen with iron?

A

Grey solid burns with oranges sparks producing a black solid

144
Q

Copper reactions ?

A

Red pink solid glows and forks a black solid

145
Q

What is sulfur ?

A

Brittle yellow solid

146
Q

Allotropes of sulfur ??

A

Rhombic sulfur
Monoclinic sulfur
Plastic sulfur

147
Q

What are allotropes ?

A

Alternative forms of the same element in the same physical state

148
Q

Sulfur and iron?

A

Yelllow sulfur and grey iron glows red when heated forming s black sold

149
Q

What is sulfur dioxide ?

A

Colourless pungent gas

150
Q

How is sulfur dioxide collected ?

A

Downward delivery

151
Q

What does acid rain do ?

A

Corrodes limestone buildings
Defoiliates trees
Pollutes lakes

152
Q

How to prevent acid rain?

A

Remove sulfur from fossil files before burning

Use renewable energy resources

153
Q

What is the contact process stages ?

A
  1. Combustion of sulfur s+O2-> SO2
  2. Catalytic production of sulfur trioxide
    450 here’s pressure of 2 atmospheres
    Catalyst of vanadium five oxide
    2SO2+ O2 ~ 2SO3
  3. Absorption in concentrated sulfur of acid
    Forms oleum
    SO3+ H2SO4 -> H2S2O7
  4. Dilution of oleum
    H2S2O7 + H2O-> 2H2SO4
154
Q

What is sulfuric acid used fo ?

A

Car batteries

155
Q

What is the chemical name for sugar ?

A

Sucrose

156
Q

Reaction of sulfuric acid and sugar ?

A

Sugar swells up and rises in container
Heat is released and there is a distinct caramel smell together with a pungent odour
A black solid is formed

157
Q

Why is water not directly added to sulfuric acid ?

A

It produces a corrosive mist

158
Q

Formula for percentage of element X in a compound?

A

Number of atoms of X in compound x RAM of x/ RFM of compound x 100

159
Q

Formula for dilution factor ?

A

Dilution factor = total volume of diluted solution / volume of original solution to be diluted

160
Q

How do you work out the number of miles of a solid in a solution ?

A

Moles = solution volume x concentration / 1000

161
Q

Colour changes of phenolphthalein ?

A

Acid to alkali - pink to colourless

Alkali to acid - colourless to pink

162
Q

Colour changes of methyl orange?

A

Acid to alkali - yellow to red/orange

Alkali to acid- red to yellow/ orange

163
Q

How do you prepare a pipette ?

A

Rinse it with deionised water
Rinse with solution to be used
Use a pipette filler to draw up the solution Neil the bottom of the meniscus is on the line

164
Q

How do you prepare a Burette?

A

Rinse with deionised water
Rinse with solution to be used
Fill burette with solution ensuring the key is filled and there are no air bubbles
Read volume at the bottom of the meniscus

165
Q

Method of titration?

A

Measure volume is put into pipette
Few drops of indicator are added to the conical flask and the solution is mixed
Burette is filled with the second solution
Second solution is run out of the Burette and into the conical flask while the conical flask is being swirled until the indicator changed colour
Volume of solution added from Burette is recorded - titre
Titration carried out three times

166
Q

What can raw materials can you get from earth?

A

Like , salt

167
Q

From the sea ?

A

Water , sodium chloride

168
Q

From the air ?

A

Oxygen and nitrogen

169
Q

From crude oil?

A

Plastics patrol

170
Q

From living things

A

Cotton wool wood

171
Q

What are natural materials ?

A

Those derived directly from raw materials

172
Q

What are synthetic materials ?

A

Those which are man made

173
Q

What is silver nitrate is used for ?

A

Wound dressings in hospitals - kill bacteria which prevents the wound from becoming infected

174
Q

How are metals high in the reactivity series extracted ?

A

Electrolysis

175
Q

How are metals low in reactivity dries extracted ?

A

Reduction with carbon

176
Q

What is an electrolyte ?

A

The liquid or solution that conducts electricity and is then decomposed by it

177
Q

What is the negative electrode called ?

A

Cathode - positive ions attract to it

178
Q

What is the positive electrode called ?

A

Anode- negative ions attracted to it

179
Q

Why do all electrolytes conduct electricity ?

A

Free ions that can move and carry charge

180
Q

What is aluminium ore ?

A

Bauxite

181
Q

What does bauxite form when purified ?

A

Alumina

182
Q

Why is alumina dissolved in molten cryolite?

A

To reduce its melting point

183
Q

What does a crust of aluminium oxide do?

A

It keeps heat in

184
Q

What are the anode and cathode made out of in extraction of aluminium from its ore ?

A

Carbon

185
Q

Why does the carbon anode have to be replaced periodically?

A

Due to its reaction with oxygen it wears away

186
Q

What is the solid material that is put into the last furnace called?

A

The charge

187
Q

What is the charge made up of ?

A

Iron ore , limestone and coke

188
Q

What is iron ore called ?

A

Haematite

189
Q

What is the reducing agent ?

A

Carbon monoxide

190
Q

What is the steps on the extraction of iron in the last furnace.

A
  1. Production of reducing agent
  2. Reduction of iron ore to iron
  3. Removal of acidic impurities
191
Q

Advantages and disadvantages of recycling ?

A

Saves resources
Fewer eyesores created
But labour intensive

192
Q

Advantages and disadvantages of disposal by incineration or landfill ?

A

Heat energy from incineration can be harnessed to generate electricity
But Landfill wastes land

193
Q

Advantages and disadvantages of production of ne material s?

A

Workforce must be skilled

But more raw materials used

194
Q

What is polymerisation?

A

The process of creating a long molecule from small molecules which form the repeating unit in the polymer

195
Q

What is addition polymerisation ?

A

The process of adding molecules together to form a polymer as the only product

196
Q

What is a monomer ?

A

He simple molecule from which a polymer is formed

197
Q

What is fermentation?

A

Sugar solution is mixed with yeast in warm conditions in the absence of oxygen to produce carbon dioxide and ethanol