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1
...
Strong forces of attraction between particles
2
...
Atoms vibrate but can’t change position therefore
fixed volume and shape
Liquid:

All substances are made of atoms, which consist of
protons, electrons and neutrons
...
Weaker attractive forces than solids
2
...
Particles slide past each
Gas:
1
...
Particles are far apart, and move quickly
3
...

• When a gas is cooled, the particles lose energy
...

• When they bump in to each other, they do not have enough energy
to bounce away again
...

• When a liquid cools, the particles slow down even more
...

Evaporation and boiling:
•
•
•
•

Evaporation constantly occurs on the surface of liquids
...

Boiling occurs at the boiling point and then the liquid evaporates
everywhere in the liquid and is much faster
...


Chemistry Diffusion
The process in which particles mix/spread by colliding randomly with each other, and bouncing off in all directions
...


Evidence of diffusion
In liquids: potassium manganate (VII) in beaker of water
...
)
In gases: a gas jar of air and a gas jar of bromine are connected, the bromine travels up the tube
...
) Experimental techniques:
Time

Temperature

Mass

Volume

Stopwatch

Thermometer

Balance

-beaker

Clock

(liquid in glass,
thermistor
thermocouple)

or

-burette
-pipettes
-measuring cylinder
-gas syringe

2
...
Three or four more drops are added to
it
...
Paper + rings = chromatogram
...
(To identify substances) Spots of
substances placed onto a pencilled line (as ink would separate) which is called
the origin, and labelled
...
There are spots which have travelled different distances
...
Dry paper in oven 2
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Heat it for 10 minutes in oven
...
g
...
The mobile phase consists
of the mixture you want to separate, dissolved in a solvent
...
This is why salt is used on roads to prevent the
formation of ice or to melt ice
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2
...
One drop is placed on a
microscope slide to check if crystals are forming
...
Crystals are filtered to remove solvent
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Residue is insoluble and stays at top
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Distillation:
•
•

•
•

Simple distillation (left picture below) evaporates a solvent from a
solution
...
Used
to separate substances in crude oil and get ethanol from the products
of fermentation
...
So
the beads are heated to the boiling point of the lowest substance in this case, so that the substance being
removed cannot condense on the beads
...
The beaker can be changed after every
fraction
...
) Atoms, elements and compounds:
3
...

Nucleon number: the number of protons + neutrons in the nucleus of an atom
...
When you go one element down, you increase the proton number by 8
in the first 3 periods (where the transition elements are not included)
...
g
...


•
•

There are non-radioactive and radioactive-isotopes
...

Medical use: cancer treatment, sterilize tools
Industrial use: to check for leaks

•

Electrons are arranged in electron shells
...

Noble gases have full outer shells so they have no need to
react
...

More reactive elements have a greater desire to have a
full outer shell, so also form more stable compounds
...


3
...
Each element has a unique proton no
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Metals:
strong
malleable and ductile
sonorous
good conductors of heat and electricity
have high melting and boiling points (except mercury)
high density
react with oxygen to form (usually) basic compounds called
metal oxides (aluminium oxide is amphoteric)
8
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some, g
...

1
...

3
...

5
...

7
...
Are brittle
2
...
Poor conductors of electricity, except for graphite
(carbon) and are also bad conductors of heat
4
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Most react with oxygen to form (usually) acidic
oxides (carbon monoxide is neutral)
6
...
g
...


3
...
They form by losing an electron which increases charge by 1, or by gaining one which decreases
charge by 1
...
A negatively charged atom is an anion, it’s a non-metal
...

• Group 1 metals react with halogens
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• An ionic compound (in solid state) has a regular arrangement (lattice) of alternating positive and negative ions
...
g
...
g
...

• When you melt an ionic solid you break up the compound into ions, so it takes more energy, therefore ionic
compounds have higher melting points
...
g
...


3
...
Used for cutting, because it is the hardest
known substance (2 left pictures below)
...
It can conduct electricity because it has one free electron
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Silicon (IV) oxide/silicon dioxide/silica: makes up most of sand
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As a result it has a high melting point and is hard, like diamond (right picture)
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General properties of giant molecules
Melting point: Very high since structure is made up of a large number of covalent bonds, all of which need to be broken if
atoms are to be separated
Electrical: Don’t conduct electricity (have no mobile ions or electrons),
Strength: Hard – exist in a rigid tetrahedral structure e
...
Diamond and silica (SiO2)
*Graphite is an exception as it conducts electricity and is soft
...
2 (d) Metallic bonding
-Metallic bonding: a lattice of tightly packed positive ions in a sea of electrons, resulting in crystals, therefore:

Metals are malleable and ductile – the layers of ions can slide
over each other
2
...


4
...

Relative molecular mass, Mr: the sum of the relative atomic masses
...
Naming
compounds:
• If only two elements are combined, the name ends in ‘–ide’
...
g
...

With covalent compounds the element further on the left goes first (hydrogen is thought of being in between
nitrogen and oxygen so: phosphorus trihydride / hydrogen peroxide)

5
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➢ Electrolyte: a molten or aqueous solution through which an electrical current can flow
...

➢ Anode (positive electrode): non-metals are formed, oxidation takes place
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e
...
g
...
g
...
g
...

-if a halide is in a concentrated solution, then a halogen
will be produced at the anode
...


Electroplating
For electroplating, you need:
1
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ions of the same metal as the anode in solution
3
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• Aluminum is used for electricity cables (not wires) because its light, doesn’t
•
•

corrode, is a good conductor, is cheaper and lighter than copper
...

Plastics and ceramics are used as insulators because they don’t conduct electricity, and conduct heat poorly
...
Ceramics are used to support the cables in electricity pylons
...
, but it is cheaper)

Choice of electrodes can affect products
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Graphite (carbon), platinum

Refining copper
This concept above is used to refine copper
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To obtain metal copper it must first be extracted from its ore by reduction (usually with carbon)
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This produces impure copper
...
Before metal can be used it must be purified by electrolysis
...
(In order to melt it, because it has high melting point)
The mixture melts at a lower temperature
...


During electrolysis aluminium is produced at the carbon cathode and oxygen at the carbon anode
...

Must use inert electrodes since products are reactive

6
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1 Energetics of a reaction
Exothermic reaction: gives out energy to the surroundings
...
Bond breaking is endothermic

Bond making is exothermic
If you subtract the energy stored in the bonds of the reactants from the product you get the change in enthalpy or ΔH
...
2 Production of energy
•

A fuel is a substance used to obtain energy
...
) to form oxides is an exothermic reaction

•

(gives out heat)
...

Hydrogen: Burns explosively with oxygen, so it is used in rockets
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Nuclear fuels: are not burned
...
In a nuclear

•

power station they are forced to break down by shooting neutrons at them
...
Advantages: lots of energy is made from a small amount of fuel and no carbon dioxide is
produced
...
The greater the difference
in reactivity of the two metals, the greater the voltage will be
...
The atoms give up electrons and enter the solution as ions
...
Chemical reactions
Collision theory: collisions are needed for a chemical reaction to take place & the successful collisions have enough energy, also
known as activation energy, at the moment of impact to break the preexisting bonds and form all new bonds
...
This is because there is more chance of reactant particles colliding, so there will be more collision per
unit of time
...
This is because many small particles will
have more surface area than fewer large particles
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More collisions per unit of time means a faster reaction
...
Catalysts work by
lowering the activation energy and providing an alternative pathway for the reaction
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-Enzymes: proteins that function as biological catalysts Factors that control how well enzymes work
• Temperature: enzymes have an optimum temperature
...
In humans, most enzymes have an optimum temperature of 37°C
...
If the temperature is
too high, the enzyme molecules vibrate too vigorously, and the enzyme is denatured: it loses its 3D shape and will no
longer bind with a substrate
...

• pH: The base or acid conditions can denature enzymes too, but the enzyme can be denatured if the pH is too low
OR too high
...
5, and pepsin’s pH 2
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particles faster, so a reaction (which needs collisions) will take less time and 2) particles will more often overcome the
activation energy
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-You measure the amount of time taken for the cross to not be
visible because there is enough Sulphur

...

-Variables that can be changed: temperature and concentration of reactants
...
-Reactions with different sized particles (e
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magnesium
powder vs
...
smaller chips)
...
g
...
) Marble is calcium carbonate
...

-Variables that can be changed: temperature and concentration of reactants
...
Large surface area can mean
danger: Flour dust, wood dust, custard powder, instant coffee, sugar, and dried milk have large surface areas, and are

combustible
...

3
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Even if you leave it for hours, no
reaction will happen
...
The gas mixture explodes
immediately with a pop, producing water
...


Light provides energy for the reaction, chlorophyll is a dye that absorbs light
...
Silver ions are
reduced to silver
...

Example: CuSO4
...
If the temperature is
raised – the equilibrium moves in the endothermic direction
...
If
the pressure is lowered the equilibrium moves to the side with most gas molecules
...
Increasing reactant concentration or decreasing product concentration moves it to the product side
...

Redox
•
•
•

Oxidation Is Loss of electrons/the gain of oxygen, Reduction Is Gain of electrons/loss of oxygen
...

Redox reaction is a reaction where reduction and oxidation happen, where there is electron transfer
...
One substance gives electron(s) to the other
...
Oxidation state is written
using roman numerals when there is a transition metal in a word equation
...
Oxidation state is written like this Iron(III) = Fe3+

(a reaction where different atoms of the same element are reduced and oxidised is a disproportionation reaction) Examples
to know
1
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Potassium mangenate, an oxidising agent, will go from purple to colourless
...
Acids, bases and salts:
8
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•

Acid turns methyl orange → red

•
•
•

Acids have are pH 6 and below
Acid + metal → metal salt + hydrogen
Acid + base (except carbonates) → salt + water

•

Acid + metal carbonate → metal salt + carbon

Bases a substance that neutralizes an acid
• Bases turn red litmus blue
...
)
-Acidity in soil: plants grow at a pH near 7
...
Acidic soil is fixed by adding lime
...

Alkali turns methyl orange → yellow
Acid + base → salt + water + (carbon dioxide
All alkalis (except ammonia) will react with
ammonium compounds, removing ammonia for
example:
calcium hydroxide + ammonium chloride →
calcium chloride + water + ammonia

When Acids React, they will Lose Electrons to Form Positive Hydrogen Ions ( H+)
These H+ Ions Makes the Aqueous Solution Acidic

Example: Hydrochloric Acid

HCl (aq) → H+ (aq) + Cl- (aq)

BASES (ALKALIS):
• When Alkalis React, they will Gain Electrons to Form Negative Hydroxide Ions ( OH- )
• These OH- Ions Makes the Aqueous Solution an Alkali

Example: Sodium Hydroxide

NaOH (aq) → Na+ (aq) + OH- (aq)

*Bases become alkali if they are
dissolved in water

Universal indicator is an indicator which can be used as paper or in solution:

Strong Acids

Strong Bases (Alkalis)

all molecules dissociate to become ions
low pH
high conductivity

high conductivity
high pH
weak bonds

weak bonds

high dissociation

Weak Acids

Weak Bases

only some molecules dissociate
higher pH,
low conductivity
strong bonds (weaker effervescence when reacting with
carbonates or metal than a strong acid)

low conductivity and pH
strong bonds therefore low dissociation In alkalis
More dissociation i
...
higher concentration of OH- ion =
higher pH
...
2 Types of oxides
•
•

In general, metal oxides are basic, and non-metal oxides are acidic
...


•

Amphoteric oxides: e
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Aluminium oxide and zinc oxide: they react with bases and acids
...
4 Identification of ions and gases

9
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• If you go down a period of metals (except TM) they become more reactive (this
is because there are more electron shell
...
)
•

With non-metals, going down a period, the non-metal becomes less reactive (the reason is the opposite than for metals
...

-Are soft, compared to other metals
...

-They have low melting and boiling points compared to most metals
...


Reactivity, density and softness increases further down the group i
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Caesium is more reactive that lithium
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Melting and boiling points decrease
...
Reactivity increases because more electron shells means there is a
less strong attraction between the nucleus and the valency electron
so it is lost more easily
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-React with cold water
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(Down the group) size, mass and density increase
(and colour darkness)
...
Reactivity decreases, because it has to gain an
electron, so the closer the electron is to the
positive nucleus the more easily it will be gained, so
atoms with fewer shells will react more easily
...
They are also:
--Good conductors of heat and electricity (silver is the best)
--Much less reactive than group one metals, except for iron which rusts easily
--Have no trend in reactivity, can form complex ions
--Can form several differently charged ions: have variable valency, therefore…
...


--They can form more than one compound with another element: FeO, Fe2O3
** Transition metals have variable oxidation states: e
...
Fe(ii), Fe (iii)

Uses:
o Helium- filling balloons and
aircrafts because it is
lighter than air and will not
catch fire
...

o anhydrous
Neon – iscopper(II)sulfate,
used in
▪
...
When you add water to
it
advertising signs because it
will turn blue
...
5H2O(s)
glows red
...

CoCl2(s) + 9H2O(l) ———–> CoCl2
...
Air and Water

The purification of the water supply by filtration and chlorination
...
It may contain bacteria, dead animals and plants, dirt etc
...

▪ Afterwards, the water is chlorinated (treated with chlorine) to get rid of bacteria and microbes that couldn’t be
removed through filtration
...

▪ Water is used in factories as a solvent for many chemicals and as a coolant to stop industrial processes from
getting too hot
...

▪ In agriculture, water is used on farms for watering crops and feeding animals
...

*Water is essential for life; it covers 2/3 of our planet
...
Water is also needed for crop irrigation, and therefore is essential for life
...
9% argon), carbon dioxide
(0
...

Common pollutants in air: Carbon monoxide (CO),Sulfur dioxide (SO2), oxides of nitrogen, lead compounds (eg PbCO3)

Pollutants sources:
▪
▪
▪
▪
▪

Carbon monoxide: incomplete combustion of fossil fuels/ carbon containing substances
Sulfur dioxide: combustion of fossil fuels (leads to acid rain)
Nitrogen oxides: nitrogen and oxygen react at high temp of combustion in car engine (also from hot frunaces)
Lead compounds: a lead compound is added to petrol to help it burn more smoothly
...
Water reacts with the iron over time and the oxygen in the
air oxidises the iron
...

4Fe(s) + 3O2(g) + 2H2O(l) ———-> 2Fe2O2
...

▪ Using a more reactive metals to protect a less reactive metal from corrosion is called sacrificial protection
...

▪ Steps 3 and 4 are repeated, cooling the air more
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These gases
are removed
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▪
▪

The liquid air is pumped into the fractioning There it is slowly warmed up
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Nitrogen oxides are produced when oxygen and nitrogen from air react in hot condit ions (in engines and furnaces)
...
Nitrogen oxides are decomposed back into nitrogen and oxygen
...

Potassium helps make proteins and resist diseases
...

All alkalis (except ammonia) will react with ammonium
compounds, removing ammonia for example:
calcium hydroxide + ammonium chloride → calcium chloride +
water + ammonia
...

▪ They stop heat escaping in to space
...
This will cause the ice poles to melt, rising
sea levels, more droughts, storms, floods and
famine
...


Fuels to know:

▪
▪
▪

•
•
•

coal
natural gas (main constituent is methane)
petroleum

Formation of carbon dioxide:
Product of respiration
COMPLETE combustion of carbon-containing substances
Reaction of an acid and a
Sources of methane: oil and natural gas, decomposition of vegetation, and waste gases from digestion in animals
...
The more reactive metal will react more
easily and be sacrificed
...
Hydrogen can be made in several ways:
•
•

Methane + steam → carbon dioxide + hydrogen
it can be cracked (using a catalyst): C2H6 → C2H4 + H2 CONDITIONS: 450°C, 200atm, iron catalyst
The forward reaction is exothermic, and the backwards reaction is
endothermic
...
Higher temperature is used for a better rate and
lower pressure for safety and it is cheaper
...


12
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It is also found around the rims of
volcanoes
...
Sulphur compounds also occur naturally in the fossil fuels: coal, oil
and natural gas
...

Uses of Sulphur dioxide
-manufacture of sulphuric acid
-to bleach wool, silk and wood pulp for making paper
-it is used as a sterilising agent in making soft drinks and jam, and in drying fruit
...

Uses of sulphuric acid: making fertilisers such as ammonium sulphate, paints, pigments, and dyestuffs, fibres and plastics,
soaps and detergent, acid in car batteries
The Contact process: sulphur → burned in air → sulphur dioxide → mixed with more air → passed over four separate
beds of catalyst (pellets of Vanadium (V) oxide) at 450°C → sulphur trioxide → dissolved in concentrated sulphuric acid →
thick fuming liquid called oleum → mixed carefully with water → concentrated sulphuric acid
...
)

13
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g
...

Uses of calcium carbonate (limestone): making cement – made by mixing

waste

limestone with clay, heating the mixture strongly in a kiln like the one below, adding gypsum (calcium sulphate), and grinding up
the final solid to give a powder (diagram page 235)
...


14 Organic Chemistry
methane

CH4

ethane

C2H6

ethene

C2H4

ethanol

C2H5OH

ethanoic

CH3COOH

acid

“ane” → alkane
“ene” → alkene “ol” → alcohol
“oic acid” → carboxylic acid
“yl”, “oate” → ester (as in ethyl ethanoate

Fuels to know:

1
...

3
...

5
...

7
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-coal
-natural gas (main constituent is methane)
-petroleum (a mixture of hydrocarbons which can be separated into fractions):
refinery gas – bottled gas for heating and cooking
gasoline fraction – fuel (petrol) in cars
naphtha fraction – making chemicals
kerosene/paraffin fraction – jet fuel, lamps
diesel oil/gas oil fraction – fuel in diesel engines
fuel oil fraction – fuel in ships and home heating systems
lubricating fraction – lubricants, waxes and polishes
bitumen – making roads
•

Homologous series: ‘family’ of similar compounds with similar properties due to the presence of the same
functional group
...

Structural isomers: have the same chemical formula, but different structures, they can be straight or branched
...
They only have two reactions:
–combustion this can either be:
–complete: meaning there is enough oxygen supply so water and carbon dioxide form
...
g
...

e
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2CH4 + 3O2 → 2CO + 4H2O or
CH4 + O2 → C + 2H2O
–chlorine substitution: sunlight is necessary (or any light?)
...
This can happen to all
of the hydrogen atoms if there is enough chlorine
...
g
...

Cracking always produces a short chain compound with a C=C bond
...

In the lab it looks like this:
Saturated hydrocarbons:
-have NO double bonds
-do not react with aqueous bromine, so the mixture stays orange
...

Poly(ethene) / Polythene: is a polymer produced from ethene by addition
polymerisation
...

Alkenes’ Addition Reactions:
-with bromine: (the test for saturation)
e
...
ethene (g) + bromine (aq) → 1,2-dibromomethane (l)
-with steam: forms alcohols with heat, pressure and a catalyst
e
...
ethene (g) + steam (g) ⇌ ethanol (l)
-with hydrogen: double bond breaks down to for an alkane with heat, pressure and a catalyst
e
...
ethene (g) + hydrogen (g) → ethane (g)

Alcohols
Ethanol can be formed in to ways:
1
...
This can be done
with any substance that contains cellulose, starch or done by grinding the source (e
...
corn or grapes) and treating it
with enzymes to break down cellulose and starch into glucose
...
Fractional distillation is used to get
the ethanol from the mixture of substances
...
Ethene is obtained by cracking long-chain alkenes from The ethene reacts with steam (reversibly) in the following
conditions: 570°C, 60-70atm and a catalyst (phosphoric acid)
...


Fermentation

From ethene

Advantages:

Advantages:

-renewable source
-good use of waste organic material (e
...
the apples which
don’t look nice enough to be sold in shops
...

-Fractional distillation is expensive

-lots of energy to make steam and get the right conditions
-a lot of ethene is un-reacted, (and then recycled)

-Slow process
Ethanol burns well in oxygen, giving out plenty of heat, as well as carbon dioxide and water
...
It evaporates easily, so it is used a solvent in glues, printing inks, perfumes
and aftershave
...

Carboxylic acids react with alcohols to give esters, in a condensation reaction, for example:
Ethanoic acid + ethanol ⇌ ethyl ethanoate + water (the alcohol’s name becomes “-yl” part and the carboxylic acid’s name
becomes the “-oate” part
...
Different macromolecules have different units
and/or different linkages
...
(NOTE: diamonds
are other examples of macromolecules)
...
Or they fill up the animals’ stomachs so that they can’t eat
proper food, and starve to death
...

-they collect in rivers, and get in the way of fish
...
So, the place looks a mess
...

Making nylon (a polyamide):
The monomers are:

But they are represented like this:

No double bonds break
...
The monomers are able to join to each other
by eliminating a small molecule: hydrogen chloride
...
Thousands of molecules
join together, giving a macromolecule:

Making Terylene (a polyester): The monomers are:

The monomers join by eliminating a water molecule
...


Natural macromolecules
Food’s main constituents are proteins, fats and carbohydrates
...
Similarly, lipids and terylene both have ester
links but different units
...

Fats are esters possessing the same linkage as Terylene (ester links) but with different units
...
It is done using sodium hydroxide (as opposed to acid, in digestion)
...
The salts are used as soaps
...
The sugar units are represented like this:

They join together in a condensation polymerisation:

In digestion, the hydrolysis (Decomposition of a chemical compound by reaction with water which can be accelerated by an
acid or base) of starch happens in the mouth by the enzyme amylase to make glucose
...
So you get a mixture of molecules of
different sizes for example for starch you get, glucose, maltose (2 glucose units) and maltotriose (3 glucose units)
...
However, amino acids and sugars are colourless
when dissolved in water, so a locating agent is used
...




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