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C6 Flashcards

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1
Q

Why is it called a redox reaction?

A

Because reduction and oxidation happens at the same time

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2
Q

What is reduction?

A

Gain of electrons

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3
Q

What is oxidation?

A

Loss of electrons

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4
Q

What is an oxidising agent?

A

One that accepts electrons and gets reduced

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5
Q

What is a reducing agent?

A

It donates electrons and gets oxidised

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6
Q

Give an example of a redox reaction

A

Iron atoms are oxidised to iron(11) ions when they react with dilute acid
Iron atoms lose electrons - they’re oxidised by the hydrogen ions
Hydrogen ions gain atoms they are reduced by the iron atoms

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7
Q

What are displacement reactions?

A

Redox reactions

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8
Q

What does a displacement reaction involve?

A

One metal kicking another metal out of a compound (reactive metal into solution of a dissolved metal compound)

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9
Q

What is the rule for a displacement reaction?

A

A more reactive metal will displace (and replace) a less reactive metal from its compound

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10
Q

Describe a displacement reaction

A

It’s always the metal ions that gain electrons and get reduced
The metal atom always loses electrons and is oxidised

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11
Q

What is the rusting of iron?

A

A redox reaction

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12
Q

When does rusting happen?

A

When the irons in contact with both oxygen and water

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13
Q

What is rust?

A

Hydrated iron (111) oxide

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14
Q

What is the word equation for rusting of iron?

A

Iron + oxygen + water = hydrated iron

(111) oxide

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15
Q

What happens in the rusting of iron?

A

Iron loses electrons when it reacts with oxygen (each iron atom loses three electrons) - oxidised
Oxygen gains electrons when it reacts with iron (each oxygen atom gains two electrons) - reduced

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16
Q

Describe metals being combined with other things to prevent rust

A

Iron can be mixed with other metals to prevent rust (alloy)
Eg Steels are alloys of iron and Carbon
- stainless steel is iron Carbon and chromium - it’s rustproof

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17
Q

Give some examples of preventing rusting by coating the iron with a barrier

A

Keeps out water, oxygen or both
Painting - ideal for large and small structures
Oiling or greasing is used when moving parts are involved (bike chains)

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18
Q

Describe a tin coating preventing rusting

A

tin plated
Tin acts as barrier stopping oxygen and water from reaching the surface of the iron
Only works if the tin remains intact (not scratched)
If tin scratched iron will lose electrons in preference to tin (because tin is less reactive than iron) and it will rust even faster than if it was on its own

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19
Q

What is the sacrificial method?

A

Placing a more reactive metal with the iron to prevent rusting - water and oxygen react with this and not the iron

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20
Q

Give two examples of the sacrificial method

A

Galvanising - coat of zinc - zinc is more reactive so loses electrons in preference to iron and acts as a barrier
Blocks of metal (magnesium) bolted to iron - used on hulls of ships or underground iron pipes

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21
Q

What does electrolysis mean?

A

Splitting up with electricity

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22
Q

Describe electrolysis

A

Electric current passed through a molten or dissolved ionic compound causing it to decompose
Creates flow of charge through electrolyte
As ions gain or lose electrons at cathode or anode they become atoms or molecules and are discharged from the solution

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23
Q

What happens at the cathode in electrolysis?

A

Positive ions move towards cathode and gain electrons

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24
Q

What happens at the anode in electrolysis?

A

Negative ions move towards anode and lose electrons

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25
Q

What can happen in the electrolysis of aqueous solutions?

A

Aqueous solutions contain ions from the water as well as ions from the solute (ionic compound)
Sometimes it’s easier to discharge the ions from the water instead of the ones from the solute depending on how easily the ions lose or gain electrons

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26
Q

What is produced at the anode and cathode in the electrolysis of aqueous sulfuric acid?

A

Hydrogen gas at cathodes

Oxygen at anode

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27
Q

What is produced at the anode and cathode during the electrolysis of Aquila sodium hydroxide solution?

A

Cathode - hydrogen gas

Anode- oxygen

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28
Q

What can copper (11) sulphate be electrolysed to form?

A

Copper and oxygen

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29
Q

What happens in the electrolysis of copper (11) sulfate solution when you use Carbon dioxide?

A

The cathode starts off as a piece of carbon but gets coated with a layer of copper (because copper ions are easier to discharge than hydrogen ions) - reduced
At the anode the hydroxide ions are discharged and converted into oxygen and water - oxidised

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30
Q

Which is the negative electrode?

A

Cathode

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31
Q

Which is the positive electrode?

A

Anode

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32
Q

What is the ionic equation for the reaction at the cathode in the electrolysis of copper (11) sulfate solution?

A

Cu2+ + 2e- -> Cu

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33
Q

What is the ionic equation for the reaction at the anode during the electrolysis of copper (11) sulfate solution?

A

4OH- - 4e- -> O2 + 2H2O

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34
Q

What happens in the electrolysis of molten ionic compounds?

A

Broke up into their elements
Positive metal ions are reduced to atoms at the cathode
Negative ions are oxidised to atoms at the anode

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35
Q

Why can molten ionic compounds be electrolysed?

A

Because the ions can move more freely

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36
Q

What is the solution that you electrolysed called?

A

Electrolyte

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37
Q

How do you increase the number of electrons transferred in electrolysis?

A

Electrolysing for a longer time

Increasing the current

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38
Q

What does increasing the amount of electrons transferred mean in electrolysis?

A

More product is produced

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39
Q

What is the amount of product produced in electrolysis proportional to?

A

Directly proportional to the time taken and current used

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40
Q

What is the amount of charge (Q- coulombs) flowing through a circuit in electrolysis equal to?

A

Current (I) multiplied by time (s)

Q=It

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41
Q

What equation can you use to work out the amount of product formed in electrolysis?

A

Q=It

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42
Q

When is it a redox reaction?

A

If electrons are transferred

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43
Q

What do fuel cells use to make electricity?

A

Hydrogen and oxygen

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44
Q

What do hydrogen and oxygen do when they react?

A

Give out energy

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45
Q

What kind of reaction is the one between hydrogen and oxygen?

A

Exothermic - releases energy

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46
Q

What does it mean when a reactions exothermic?

A

Less energy is taken to break bonds than is released in making bonds

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47
Q

What is a fuel cell?

A

An electrical cell that’s supplied with a fuel and oxygen ad uses energy from the reaction between them to produce electrical energy efficiently

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48
Q

What does hydrogen-oxygen fuel cell do?

A

Combines hydrogen and oxygen to release heat energy and water - no nasty pollutants

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49
Q

What reaction do hydrogen-oxygen fuel cells involve?

A

A redox reaction

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50
Q

What electrolyte is used in a hydrogen-oxygen fuel cell?

A

Potassium hydroxide

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51
Q

What electrodes are used in a hydrogen-oxygen fuel cell?

A

Porous Carbon with a catalyst

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52
Q

What happens at the cathode in a hydrogen-oxygen fuel cell?

A

Oxygen gains electrons (reduction) and reacts with water to make OH-
O2 + 4e- + H2O -> 4OH-

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53
Q

What happens at the anode in a hydrogen-oxygen fuel cell?

A

Hydrogen (loses electrons - oxidation) combines with hydroxide ions to produce water and electrons
2H2 + 4OH- -> 4H2O + 4e-

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54
Q

How does a hydrogen-oxygen fuel cell make electricity?

A

The electrons released by the hydrogen gas at the anode flow through an external circuit from the anode to the cathode (to react with oxygen) creating the electric current

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55
Q

What is the overall reactions equation in a hydrogen-oxygen fuel cell?

A

Hydrogen + oxygen -> water

2H2 + O2 -> 2H2O

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56
Q

What are the advantages of hydrogen-oxygen fuel cells?

A

Much more efficient than power stations or batteries (efficiency can be 80%)
Electricity generated directly from the reaction (direct energy transfer) so no turbines or generators
Aren’t a lot of stages so fewer places for energy to be lost
No moving parts so energy isn’t lost as friction
Only product is water - no pollution

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57
Q

What are the disadvantage s of hydrogen-oxygen fuel cells?

A

Producing hydrogen needed requires a lot of energy - may have come from burning fossil fuels - pollution
Often contain poisonous catalysts which eventually have to be disposed of - takes time and money and can cause environmental problems

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58
Q

Where are hydrogen-oxygen fuel cells used?

A

To provide electrical power in spacecraft

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59
Q

Why are hydrogen-oxygen fuel cells used in space craft?

A 
Hydrogen and oxygen readily available from the rocket fuel tanks 
Lightweight and compact 
No moving parts that could go wrong
The product is used as drinking water 
No other waste products to get rid of
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60
Q

Why is the car industry developing fuel cells?

A

Replace conventional petrol/Diesel engines
Fuel cells don’t produce pollution - good for cities with air pollution issues
Hydrogen can be obtained from decomposing water so large amount available

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61
Q

What are CFCs?

A

Chlorofluorocarbons

Organic molecules containing Carbon, chlorine and fluorine

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62
Q

What are the advantages of CFCs?

A 
Non-toxic
Non-flammable
Chemically inert
Insoluble in water
Low boiling points 
-ideal for many uses
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63
Q

What were CFCs used in?

A

Coolants in refrigerators and air conditioning systems

Propellants in aerosols

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64
Q

When did scientists discover that chlorine helps destroy ozone?

A

1974

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65
Q

When did scientists find evidence of decreasing ozone levels over Antarctica?

A

1985

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66
Q

What supports the hypothesis that CFCs destroy ozone?

A

High levels of compounds produced by the breakdown of CFCs in the upper atmosphere

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67
Q

What is ozone?

A

A form of oxygen (O3 - three oxygen atoms) that is in the stratosphere in the ozone layer

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68
Q

What does ozone do?

A

Absorbs ultraviolet light from the sun
Absorbs UV light and breaks down into oxygen molecule and an oxygen atom
O3 + UV -> O + O2
Oxygen molecule and oxygen atom join to make ozone again
O + O2 -> O3
Natural balance

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69
Q

What does reducing the amount of ozone in the stratosphere cause?

A

More UV light hitting the surface of the earth

Increased risk of sunburn and skin cancer

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70
Q

Which countries banned CFCs as aerosol propellants in 1978?

A

USA
Canada
Sweden
Norway

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71
Q

What happened after the ozone hole was discovered?

A

Many countries got together and decided to reduce CFC production and eventually ban them altogether

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72
Q

How are free radicals made?

A

By breaking covalent bonds evenly so each atom gets one of the shared electrons making the free radical very, very reactive because of the unpaired electron (unpaired electron showed by dot •)

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73
Q

What does UV light do to the Carbon-chlorine bonds in CFCs?

A

Break to form free radicals

Only happens in the stratosphere where UV light is stronger

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74
Q

What is the equation for the breaking up of CFCs?

A

CCl2F2 -> CClF2• + Cl•

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75
Q

Why are the chlorine free radicals dangerous?

A

React with ozone turning into ordinary oxygen and chlorine oxide (free radical) which then reacts with more ozone to make two oxygen molecules and another Cl• free radical
Chain reaction so just one chlorine free radical can break up lots of ozone
Chlorine atoms aren’t used up so just carry on

76
Q

What are the equations for the chlorine free radicals destruction?

A

O3 + Cl• -> ClO• + O2

ClO• + O3 -> 2O2 + Cl•

77
Q

Why do CFCs stay in the stratosphere for ages?

A

Not very reactive so only react with one or two chemicals in the atmosphere and will only break up in the stratosphere

78
Q

What are safe alternatives to CFCs?

A

Alkanes and Hydrofluorocarbons (HFCs)

79
Q

How can you tell if it’s hard water?

A

It makes a scum with soap

It forms limescale

80
Q

Why is limescale bad in your kettle?

A

It’s a thermal insulator so it will take longer to boil

(also can eventually block pipes)

81
Q

What is hard water caused by?

A

Calcium ions and magnesium ions

As water flows of rocks containing calcium and magnesium compounds these dissolve in it

82
Q

What is the only way calcium carbonate gets into water?

A

Calcium carbonate is insoluble but will react with acids and rainwater is slightly acidic because of the CO2 from the air dissolved in it so it reacts to form calcium hydrogencarbonate

83
Q

What is the equation for rainwater reacting with calcium carbonate?

A

Carbon dioxide + water + calcium carbonate -> calcium hydrogencarbonate

84
Q

What do fuel cells use to make electricity?

A

Hydrogen and oxygen

85
Q

What do hydrogen and oxygen do when they react?

A

Give out energy

86
Q

What kind of reaction is the one between hydrogen and oxygen?

A

Exothermic - releases energy

87
Q

What does it mean when a reactions exothermic?

A

Less energy is taken to break bonds than is released in making bonds

88
Q

What is a fuel cell?

A

An electrical cell that’s supplied with a fuel and oxygen ad uses energy from the reaction between them to produce electrical energy efficiently

89
Q

What does hydrogen-oxygen fuel cell do?

A

Combines hydrogen and oxygen to release heat energy and water - no nasty pollutants

90
Q

What reaction do hydrogen-oxygen fuel cells involve?

A

A redox reaction

91
Q

What electrolyte is used in a hydrogen-oxygen fuel cell?

A

Potassium hydroxide

92
Q

What electrodes are used in a hydrogen-oxygen fuel cell?

A

Porous Carbon with a catalyst

93
Q

What happens at the cathode in a hydrogen-oxygen fuel cell?

A

Oxygen gains electrons (reduction) and reacts with water to make OH-
O2 + 4e- + H2O -> 4OH-

94
Q

What happens at the anode in a hydrogen-oxygen fuel cell?

A

Hydrogen (loses electrons - oxidation) combines with hydroxide ions to produce water and electrons
2H2 + 4OH- -> 4H2O + 4e-

95
Q

How does a hydrogen-oxygen fuel cell make electricity?

A

The electrons released by the hydrogen gas at the anode flow through an external circuit from the anode to the cathode (to react with oxygen) creating the electric current

96
Q

What is the overall reactions equation in a hydrogen-oxygen fuel cell?

A

Hydrogen + oxygen -> water

2H2 + O2 -> 2H2O

97
Q

What are the advantages of hydrogen-oxygen fuel cells?

A

Much more efficient than power stations or batteries (efficiency can be 80%)
Electricity generated directly from the reaction (direct energy transfer) so no turbines or generators
Aren’t a lot of stages so fewer places for energy to be lost
No moving parts so energy isn’t lost as friction
Only product is water - no pollution

98
Q

What are the disadvantage s of hydrogen-oxygen fuel cells?

A

Producing hydrogen needed requires a lot of energy - may have come from burning fossil fuels - pollution
Often contain poisonous catalysts which eventually have to be disposed of - takes time and money and can cause environmental problems

99
Q

Where are hydrogen-oxygen fuel cells used?

A

To provide electrical power in spacecraft

100
Q

Why are hydrogen-oxygen fuel cells used in space craft?

A 
Hydrogen and oxygen readily available from the rocket fuel tanks 
Lightweight and compact 
No moving parts that could go wrong
The product is used as drinking water 
No other waste products to get rid of
101
Q

Why is the car industry developing fuel cells?

A

Replace conventional petrol/Diesel engines
Fuel cells don’t produce pollution - good for cities with air pollution issues
Hydrogen can be obtained from decomposing water so large amount available

102
Q

What are CFCs?

A

Chlorofluorocarbons

Organic molecules containing Carbon, chlorine and fluorine

103
Q

What are the advantages of CFCs?

A 
Non-toxic
Non-flammable
Chemically inert
Insoluble in water
Low boiling points 
-ideal for many uses
104
Q

What were CFCs used in?

A

Coolants in refrigerators and air conditioning systems

Propellants in aerosols

105
Q

When did scientists discover that chlorine helps destroy ozone?

A

1974

106
Q

When did scientists find evidence of decreasing ozone levels over Antarctica?

A

1985

107
Q

What supports the hypothesis that CFCs destroy ozone?

A

High levels of compounds produced by the breakdown of CFCs in the upper atmosphere

108
Q

What is ozone?

A

A form of oxygen (O3 - three oxygen atoms) that is in the stratosphere in the ozone layer

109
Q

What does ozone do?

A

Absorbs ultraviolet light from the sun
Absorbs UV light and breaks down into oxygen molecule and an oxygen atom
O3 + UV -> O + O2
Oxygen molecule and oxygen atom join to make ozone again
O + O2 -> O3
Natural balance

110
Q

What does reducing the amount of ozone in the stratosphere cause?

A

More UV light hitting the surface of the earth

Increased risk of sunburn and skin cancer

111
Q

Which countries banned CFCs as aerosol propellants in 1978?

A

USA
Canada
Sweden
Norway

112
Q

What happened after the ozone hole was discovered?

A

Many countries got together and decided to reduce CFC production and eventually ban them altogether

113
Q

How are free radicals made?

A

By breaking covalent bonds evenly so each atom gets one of the shared electrons making the free radical very, very reactive because of the unpaired electron (unpaired electron showed by dot •)

114
Q

What does UV light do to the Carbon-chlorine bonds in CFCs?

A

Break to form free radicals

Only happens in the stratosphere where UV light is stronger

115
Q

What is the equation for the breaking up of CFCs?

A

CCl2F2 -> CClF2• + Cl•

116
Q

Why are the chlorine free radicals dangerous?

A

React with ozone turning into ordinary oxygen and chlorine oxide (free radical) which then reacts with more ozone to make two oxygen molecules and another Cl• free radical
Chain reaction so just one chlorine free radical can break up lots of ozone
Chlorine atoms aren’t used up so just carry on

117
Q

What are the equations for the chlorine free radicals destruction?

A

O3 + Cl• -> ClO• + O2

ClO• + O3 -> 2O2 + Cl•

118
Q

Why do CFCs stay in the stratosphere for ages?

A

Not very reactive so only react with one or two chemicals in the atmosphere and will only break up in the stratosphere

119
Q

What are safe alternatives to CFCs?

A

Alkanes and Hydrofluorocarbons (HFCs)

120
Q

How can you tell if it’s hard water?

A

It makes a scum with soap

It forms limescale

121
Q

Why is limescale bad in your kettle?

A

It’s a thermal insulator so it will take longer to boil

(also can eventually block pipes)

122
Q

What is hard water caused by?

A

Calcium ions and magnesium ions

As water flows of rocks containing calcium and magnesium compounds these dissolve in it

123
Q

What is the only way calcium carbonate gets into water?

A

Calcium carbonate is insoluble but will react with acids and rainwater is slightly acidic because of the CO2 from the air dissolved in it so it reacts to form calcium hydrogencarbonate

124
Q

What is the equation for rainwater reacting with calcium carbonate?

A

Carbon dioxide + water + calcium carbonate -> calcium hydrogencarbonate

125
Q

What are the two kinds of hardness?

A

Temporary hardness

Permanent hardness

126
Q

What is temporary hardness caused by?

A

The hydrogencarbonate ion

127
Q

What is permanent hardness caused by?

A

Dissolved calcium sulfate

128
Q

How is temporary hardness removed?

A

By boiling

The calcium hydrogencarbonate decides to form insoluble calcium carbonate

129
Q

What is the equation for boiling temporary hardness water?

A

Calcium hydrogencarbonate
->
Calcium carbonate + water + carbon dioxide
Ca(HCO3)2 -> CaCO3 + H2O + CO2

130
Q

How can both types of hardness be removed?

A

Adding washing soda (sodium carbonate) - carbonate ions join to calcium ions making an insoluble precipitate of calcium carbonate
Ion exchange resin - lots of sodium or hydrogen ions are exchanged for calcium or magnesium ions

131
Q

What is the equation for removing hardness by adding washing soda?

A

Ca2+ + CO32- -> CaCO3

132
Q

Describe an experiment that compares the hardness of water samples

A

Add 100cm3 of water to conical flask
Add 1cm3 soap solution
Put a bung in and shake
Keep adding soap until a good lasting lather has formed (bubbles cover surface for at least 30 seconds)
Record how much soap needed
Then repeat this time boiling the water first to see of hardness is temporary or not

133
Q

What is the general formula of an alcohol?

A

C(n)H(2n+1)OH

134
Q

What makes ethanol?

A

Fermentation

135
Q

What is the word equation for fermentation?

A

Glucose -> ethanol + Carbon dioxide

136
Q

What is the symbol equation for fermentation?

A

C6H12O6 -> 2C2H5OH + 2CO2

137
Q

How is fermentation used?

A

To convert sugars into ethanol - the reaction is caused by enzymes found in yeast

138
Q

What conditions are needed for fermentation?

A

Temperature carefully controlled to prevent denaturing and inactive-ness (too cold) - carried out at optimum - between 25 and 50 degrees
Prevent oxygen from interfering as this will convert ethanol into ethanoic acid

139
Q

How is pure ethanol got from the products of fermentation?

A

Fractional distillation

140
Q

How is ethanol made industrially?

A

By hydrating ethene

141
Q

Describe the industrial process for making ethanol

A

Ethene reacts with steam to make ethanol
Needs 300 degrees C and pressure of 70 atmospheres
Reaction sped up by being passed over a heated phosphoric acid catalyst

142
Q

What is the word equation for the hydration of ethene?

A

Ethene + water (steam) -> ethanol

143
Q

What is the symbol equation for the hydration of ethene?

A

C2H4 + H2O -> C2H5OH

144
Q

Compare the two ways of manufacturing ethanol

A

Fermentation is a batch process - slow and inefficient
Ethene hydration is a continuous process - ethanol made quicker but is more expensive to run because requires harsher conditions

145
Q

Compare the two ways of making ethanol by sustainability

A

Ethanol made by fermentation is a renewable fuel made from renewable sources
Hydration is non renewable made from crude oil

146
Q

Compare the two ways of making ethanol by purity

A

Ethanol by fermentation isn’t very pure and has to be distilled
Hydration has a higher purity

147
Q

Compare the two ways of making ethanol by atom economy

A

Fermentation has a lower atom economy than hydration

148
Q

Compare the two ways of making ethanol by percentage yield

A

Yield of hydration is low but by recycling unused products it has a 95% yield
Yields achieved by fermentation are much lower

149
Q

Where do fats and oils come from?

A

Annals or plants

150
Q

Give some examples of animal fats and oils

A

Lard (pork fat)
Blubber (whale fat)
Ghee (butter oil)
Cod liver oil

151
Q

Give some examples of plants fats and oils

A

Walnut oil
Coconut oil
Olive oil
Soya oil

152
Q

What happens to fats and oils at room temperature?

A

Fats are solid

Oils are liquid

153
Q

What are fats and oils?

A

Esters (what you get when you react an acid with an alcohol)

154
Q

How are fats and oils produced?

A

When an alcohol (glycerol) reacts with fatty acids

155
Q

Why are natural fats and oils important raw materials for the chemical industries?

A

Can be used as alternatives to chemicals made from crude oil
Used in
Paints, machine lubricants, detergents and cosmetics

156
Q

What are emulsions made from?

A

Oil and water

Have to be shaken vigorously to mix so the oil is broken into small drops which diapers throughout the water

157
Q

What does immiscible mean?

A

Doesn’t mix in water

158
Q

Which out of oils and fats is immiscible?

A

Oils

159
Q

What is an oil in water emulsion?

A

Oil droplets suspended in water

Eg milk

160
Q

What is a water in oil suspension?

A

Water droplets suspended in oil

Eg butter

161
Q

What can vegetable oils be used to make?

A

Biodiesel

Oils such as rapeseed and soybean can be processed and turned into fuels because they provide a lot of energy

162
Q

What are fats and oils used to make?

A

Soaps

163
Q

How do fats and oils make soap?

A

Vegetable oils react with alkali to make soap
Natural fats and oils are boiled with sodium hydroxide - the hot sodium hydroxide splits them up to produce soap and glycerol - saponification

164
Q

Describe saponification

A

Fat or oil broken up to release glycerol and fatty acids - hydrolysis
Then fatty acids react with the sodium hydroxide to make soap

165
Q

What is the word equation for making soap?

A

Fat + sodium hydroxide -> soap +

Glycerol

166
Q

What do fats and oils contain?

A

Long chain molecules with lots f Carbon atoms

167
Q

What can fats and oils be?

A

Saturated or unsaturated

168
Q

What are monounsaturated fats?

A

Ones which contain one double bond somewhere in their Carbon chains

169
Q

What are polyunsaturated fats?

A

Ones which contain more than one double bond

170
Q

How do detect whether it’s saturated or unsaturated

A

Bromine water test
Saturated and the bromine water stays orange
Unsaturated and and addition reaction will take place making a colourless dibromo compound and the bromine water is decolourised

171
Q

What can unsaturated oils be?

A

Hydrogented

172
Q

Describe hydrogenation

A

Hardening unsaturated oils by reacting them with hydrogen in the presence of a nickel catalyst at 60 degrees
- hydrogen reacts with the double bond

173
Q

How is margarine made?

A

Partially hydrogenating unsaturated vegetable oil - so it’s easy to spread (hydrogenating all and it would be too hard)

174
Q

Why are saturated fats less healthy than unsaturated fats?

A

Saturated fats increase the amount of cholesterol in the blood - increasing risk of heart disease

175
Q

What do natural unsaturated oils do?

A

Reduce the amount of blood cholesterol

176
Q

What do vegetable fats and oils tend to be?

A

Unsaturated

177
Q

What do animal fats and oils tend to be?

A

Saturated

178
Q

What does partially hydrogenated vegetable oil do?

A

Increase amount of bad cholesterol and decrease amount of food cholesterol - increase risk of heart disease

179
Q

What do detergents and soaps have?

A

A hydrophobic tail and a hydrophilic head

180
Q

What is the hydrophobic tail of a detergent molecule usually?

A

A long hydrocarbon chain

181
Q

What is the hydrophilic head of a detergent molecule usually?

A

Small and ionic

182
Q

How do detergents remove oil?

A

Hydrophobic tail forms string intermolecular forces with fats and oils and hydrophilic head with water molecules so surround the fat and oil droplets on clothes and lift them out of the fabric

183
Q

What is dry cleaning?

A

Any cleaning process that uses other solvents instead of water

184
Q

Why are solvents better at removing oil and grease than detergents?

A

They completely dissolve them
Weak intermolecular forces between solvent molecules and between grease molecules
Grease molecules are surrounded by solvent because intermolecular forces formed between them so when solvent removed the grease is removed as well

185
Q

What do biological detergents contain?

A

Biological catalysts that help break down large insoluble molecules into small soluble molecules

186
Q

Why are biological detergents good?

A

Wash at lower temperatures so not denatured enzymes - saves money
(40 degrees C)
Can wash more delicate clothes in washing machine because washing at a cooler temperature

Chemistry 1 (4 decks)

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