25/03/22 AQA Chemistry 2 AQA Chemistry 2 A slideshow that covers the entire AQA 2006 Syllabus Chemistry 2 Module W Richards
Dec 31, 2015
19/04/23
AQA Chemistry 2AQA Chemistry 2
A slideshow that covers the entire AQA 2006 Syllabus Chemistry 2 Module
W Richards
19/04/23
The structure of the atomThe structure of the atom
ELECTRON – negative,
mass nearly nothingPROTON –
positive, same mass as neutron
(“1”)
NEUTRON – neutral,
same mass as proton
(“1”)
The Ancient Greeks used to believe that everything was made up of very small
particles. I did some experiments in 1808 that proved this and called these particles
ATOMS:
Dalton
19/04/23
Mass and atomic numberMass and atomic number
Particle Relative Mass Relative Charge
Proton 1 +1
Neutron 1 0
Electron Very small -1
MASS NUMBER = number of protons + number of neutrons
SYMBOL
PROTON NUMBER = number of protons (obviously)
19/04/23IsotopesIsotopesAn isotope is an atom with a different number of neutrons:
Each isotope has 8 protons – if it didn’t then it just wouldn’t be oxygen any more.
Notice that the mass number is different. How many neutrons does each isotope have?
19/04/23
Electron structureElectron structureConsider an atom of Potassium:
Potassium has 19 electrons. These electrons occupy specific energy levels “shells”…
Nucleus
The inner shell has __ electrons
The next shell has __ electrons
The next shell has __ electrons
The next shell has the remaining __ electron
Electron structure
= 2,8,8,1
19/04/23
Mendeleev
Periodic tablePeriodic table
The periodic table arranges all the elements in groups according to their properties.
Horizontal rows are called PERIODS
Vertical columns are called GROUPS
19/04/23
H He
Li Be B C N O F Ne
NaMg
Al Si P S Cl Ar
K Ca Fe Ni Cu Zn Br Kr
Ag I Xe
Pt Au Hg
The Periodic TableThe Periodic TableFact 1: Elements in the same group have the same number of electrons in the outer
shell (this corresponds to their group number)
E.g. all group 1 metals have __ electron in their outer shell
These elements have __ electrons in their outer shell
These elements have __ electrons in their outer shells
19/04/23
H He
Li Be B C N O F Ne
NaMg
Al Si P S Cl Ar
K Ca Fe Ni Cu Zn Br Kr
Ag I Xe
Pt Au Hg
The Periodic TableThe Periodic TableFact 2: As you move down through the periods an extra electron shell is added:
E.g. Lithium has 3 electron in the configuration 2,1
Potassium has 19 electrons in the configuration __,__,__,__
Sodium has 11 electrons in the configuration 2,8,1
19/04/23
H He
Li Be B C N O F Ne
NaMg
Al Si P S Cl Ar
K Ca Fe Ni Cu Zn Br Kr
Ag I Xe
Pt Au Hg
The Periodic TableThe Periodic TableFact 3: Most of the elements are metals:
These elements are metals
This line divides metals from non-metals
These elements are non-metals
19/04/23
H He
Li Be B C N O F Ne
NaMg
Al Si P S Cl Ar
K Ca Fe Ni Cu Zn Br Kr
Ag I Xe
Pt Au Hg
The Periodic TableThe Periodic TableFact 4: (Most important) All of the
elements in the same group have similar PROPERTIES. This is how I thought of the
periodic table in the first place. This is called PERIODICITY.
E.g. consider the group 1 metals. They all:
1) Are soft
2) Can be easily cut with a knife
3) React with water
19/04/23
CompoundsCompounds
Compounds are formed when two or more elements are chemically combined. Some examples:
Glucose
Methane
Sodium chloride (salt)
19/04/23
Some simple compounds…Some simple compounds…
Methane, CH4 Water, H2O
Carbon dioxide, CO2
Ethyne, C2H2Sulphuric
acid, H2SO4
Key
Hydrogen
Oxygen
Carbon
Sulphur
19/04/23
Balancing equationsBalancing equationsConsider the following reaction:
Na
O
H HH H
Na
OH
Sodium + water sodium hydroxide + hydrogen
+ +
This equation doesn’t balance – there are 2 hydrogen atoms on the left hand side (the “reactants” and 3 on the right hand side (the “products”)
19/04/23
Balancing equationsBalancing equationsWe need to balance the equation:
Na
O
H H
H H
Na
OH
Sodium + water sodium hydroxide + hydrogen
+ +
Na
O
H HNa
OH
Now the equation is balanced, and we can write it as:
2Na(s) + 2H2O(l) 2NaOH(aq) + H2(g)
19/04/23
Some examplesSome examples
Mg + O2
Zn + HCl
Fe + Cl2
NaOH + HCl
CH4 + O2
Ca + H2O
NaOH + H2SO4
CH3OH + O2
MgO
ZnCl2 + H2
FeCl3
NaCl + H2O
CO2 + H2O
Ca(OH)2 + H2
Na2SO4 + H2O
CO2 + H2O
2
2
2 3
2
2
2
2 3
2
2
2
2
2 4
19/04/23
BondingBonding
Hi. My name’s Johnny Chlorine. I’m in Group 7, so I have 7 electrons in my outer
shell
I’d quite like to have a full outer shell. To do this I need to GAIN an electron. Who can
help me?
Cl
Cl
19/04/23
BondingBondingHere comes one of my friends,
Harry Hydrogen
Hey Johnny. I’ve only got one electron but it’s really close to my nucleus so I don’t want to
lose it. Fancy sharing?
Cl
H
Cl
H
Now we’re both really stable. We’ve formed a covalent bond.
19/04/23
BondingBondingHere comes another friend,
Sophie Sodium
Hey Johnny. I’m in Group 1 so I have one electron in my outer
shell. Unlike Harry, this electron is far away from the nucleus so I’m
quite happy to get rid of it. Do you want it?
Cl
Now we’ve both got full outer shells and we’ve both gained a charge. We’ve formed an IONIC
bond.
Na
Okay
Cl
Na
+-
19/04/23
Covalent bondingCovalent bondingConsider an atom of hydrogen:
Notice that hydrogen has just __ electron in its outer shell. A full (inner) shell would have __ electrons, so two hydrogen atoms get together and “_____” their electrons:
Now they both have a ____ outer shell and are more _____. The formula for this molecule is H2.
When two or more atoms bond by sharing electrons we call it ____________ BONDING. This type of bonding normally occurs between _______ atoms. It causes the atoms in a molecule to be held together very strongly but there are ____ forces between individual molecules. This is why covalently-bonded molecules have low melting and boiling points (i.e. they are usually ____ or ______).
Words – gas, covalent, non-metal, 1, 2, liquid, share, full, weak, stable
19/04/23
Dot and cross diagramsDot and cross diagramsWater, H2O:
Oxygen, O2:
OH H
O O
H
H
O
O O
Step 1: Draw the atoms with their outer shell:
Step 2: Put the atoms together and check they all have a full outer shell:
19/04/23
Dot and cross diagramsDot and cross diagramsNitrogen, N2:
Carbon dioxide, CO2:Ammonia NH3:
Methane CH4:
H HN
H
HH
H
H
CN N
O OC
19/04/23Other ways of drawing covalent Other ways of drawing covalent bondsbonds
Consider ammonia (NH3):
H HN
HH HN
HH HN
H
19/04/23
IonsIonsAn ion is formed when an atom gains or loses electrons and becomes charged:
If we “take away” the electron we’re left with just a positive charge:
This is called an ion (in this case, a positive hydrogen ion)
+-
+
The electron is negatively charged
The proton is positively charged
+
19/04/23
Ionic bondingIonic bonding
Na
Na
+
This is where a metal bonds with a non-metal (usually). Instead of sharing the electrons one of the atoms “_____” one or more electrons to the other. For example, consider sodium and chlorine:
Sodium has 1 electron on its outer shell and chlorine has 7, so if sodium gives its electron to chlorine they both have a ___ outer shell and are ______.
A _______ charged sodium ion
A _________ charged chloride ion
As opposed to covalent bonds, ionic bonds form strong forces of attraction between different ions due to their opposite ______, causing GIANT IONIC STRUCTURES to form (e.g sodium chloride) with ______ melting and boiling points:
Cl
Cl
-
19/04/23
Some examplesSome examples
Mg
Magnesium chloride:
MgCl2
Cl
Cl
+ Mg
2+
Cl
-
Cl
-
Calcium oxide:
CaO
OCa + Ca
2+
O
2-
19/04/23
Giant structures (Giant structures (““latticeslattices””))
+
+
+
+
+++
+
+
1. Diamond – a giant covalent structure with a very ____ melting point due to ______ bonds between carbon atoms
2. Graphite – carbon atoms arranged in a layered structure, with free _______ in between each layer enabling carbon to conduct _________
3. Sodium chloride – a giant ionic lattice with _____ melting and boiling points due to ______ forces of attraction. Can conduct electricity when _______.
4. Metals – the __________ in metals are free to move around (“delocalised”), holding the _____ together and enabling it to conduct _________
19/04/23
A closer look at metalsA closer look at metals
+
+
+
+
+++
+
+Metals are defined as elements that readily lose electrons to form positive ions. There are a number of ways of drawing them:
+-
+-
+-
+- + - +-
+-
+-
+ + +
+ + +
+ +
Delocalised electrons
19/04/23
NanoscienceNanoscience
Nanoscience is a new branch of science that refers to structures built from a few hundred atoms and are 1-100nm big. They show different properties to the same materials in bulk. They also have a large surface area to volume ratio and their properties could lead to new developments in computers, building materials etc.
Definition:
Task: research nanoscience and find two current and/or future applications of this science.
19/04/23
Group 1 – The alkali metalsGroup 1 – The alkali metals
1) These metals all have ___ electron in their outer shell.
Some facts…
2) Reactivity increases as you go _______ the group. This is because the electrons are further away from the _______ every time a _____ is added, so they are given up more easily.
3) They all react with water to form an alkali (hence their name) and __________, e.g:
Words – down, one, shell, hydrogen, nucleus, decreases
Potassium + water potassium hydroxide + hydrogen
2K(s) + 2H2O(l) 2KOH(aq) + H2(g)
2) Density increases as you go down the group, while melting point ________
19/04/23
Group 0 – The Noble gasesGroup 0 – The Noble gasesSome facts…
1) All of the noble gases have a full outer shell, so they are very ______2) They all have _____ melting and boiling points
3) They exist as single atoms rather then _________ molecules
4) Helium is ________ then air and is used in balloons and airships (as well as for talking in a silly voice)
5) Argon is used in light bulbs (because it is so unreactive) and argon , krypton and ____ are used in fancy lights
Words – neon, stable, low, diatomic, lighter
19/04/23
Group 7 – The HalogensGroup 7 – The HalogensSome facts…
1) Reactivity DECREASES as you go down the group
Decre
asin
greactiv
ity
(This is because the electrons are further away from the nucleus and so any extra electrons aren’t attracted as much).
2) They exist as diatomic molecules (so that they both have a full outer shell):
Cl Cl
3) Because of this fluorine and chlorine are liquid at room temperature and bromine is a gas
19/04/23The halogens – some The halogens – some reactionsreactions
1) Halogen + metal:
Na
+
Cl
-
Na Cl+
2) Halogen + non-metal:
H Cl+ Cl H
Halogen + metal ionic salt
Halogen + non-metal covalent molecule
19/04/23Atomic massAtomic mass
SYMBOL
PROTON NUMBER = number of protons (obviously)
RELATIVE ATOMIC MASS, Ar
(“Mass number”) = number of protons + number of neutrons
19/04/23Relative formula mass, MRelative formula mass, Mrr
The relative formula mass of a compound is the relative atomic masses of all the elements in the compound added together.
E.g. water H2O:
Therefore Mr for water = 16 + (2x1) = 18
Work out Mr for the following compounds:
1) HCl
2) NaOH
3) MgCl2
4) H2SO4
5) K2CO3
H=1, Cl=35 so Mr = 36
Na=23, O=16, H=1 so Mr = 40
Mg=24, Cl=35 so Mr = 24+(2x35) = 94
H=1, S=32, O=16 so Mr = (2x1)+32+(4x16) = 98
K=39, C=12, O=16 so Mr = (2x39)+12+(3x16) = 138
Relative atomic mass of O = 16
Relative atomic mass of H = 1
19/04/23
A “Mole”A “Mole”Definition:
A mole of a substance is the relative formula mass of that substance in grams
For example, 12g of carbon would be 1 mole of carbon...
...and 44g of carbon dioxide (CO2) would be 1 mole etc...
19/04/23Calculating percentage Calculating percentage massmass
If you can work out Mr then this bit is easy…
Calculate the percentage mass of magnesium in magnesium oxide, MgO:
Ar for magnesium = 24 Ar for oxygen = 16
Mr for magnesium oxide = 24 + 16 = 40
Therefore percentage mass = 24/40 x 100% = 60%
Percentage mass (%) =
Mass of element Ar
Relative formula mass Mr
x100%
Calculate the percentage mass of the following:
1) Hydrogen in hydrochloric acid, HCl
2) Potassium in potassium chloride, KCl
3) Calcium in calcium chloride, CaCl2
4) Oxygen in water, H2O
19/04/23
Recap questionsRecap questionsWork out the relative formula mass of:
1) Carbon dioxide CO2
2) Calcium oxide CaO
3) Methane CH4
Work out the percentage mass of:
1) Carbon in carbon dioxide CO2
2) Calcium in calcium oxide CaO
3) Hydrogen in methane CH4
19/04/23Calculating the mass of a Calculating the mass of a productproduct
E.g. what mass of magnesium oxide is produced when 60g of magnesium is burned in air?
Step 1: READ the equation:
2Mg + O2 2MgO
IGNORE the oxygen in step 2 – the question
doesn’t ask for it
Step 3: LEARN and APPLY the following 3 points:
1) 48g of Mg makes 80g of MgO
2) 1g of Mg makes 80/48 = 1.66g of MgO
3) 60g of Mg makes 1.66 x 60 = 100g of MgO
Step 2: WORK OUT the relative formula masses (Mr):
2Mg = 2 x 24 = 48 2MgO = 2 x (24+16) = 80
19/04/23
Work out Mr: 2H2O = 2 x ((2x1)+16) = 36 2H2 = 2x2 = 4
1. 36g of water produces 4g of hydrogen
2. So 1g of water produces 4/36 = 0.11g of hydrogen
3. 6g of water will produce (4/36) x 6 = 0.66g of hydrogen
Mr: 2Ca = 2x40 = 80 2CaO = 2 x (40+16) = 112
80g produces 112g so 10g produces (112/80) x 10 = 14g of CaO
Mr: 2Al2O3 = 2x((2x27)+(3x16)) = 204 4Al = 4x27 = 108
204g produces 108g so 100g produces (108/204) x 100 = 52.9g of Al2O3
1) When water is electrolysed it breaks down into hydrogen and oxygen:
2H2O 2H2 + O2
What mass of hydrogen is produced by the electrolysis of 6g of water?
3) What mass of aluminium is produced from 100g of aluminium oxide?
2Al2O3 4Al + 3O2
2) What mass of calcium oxide is produced when 10g of calcium burns?
2Ca + O2 2CaO
19/04/23Another methodAnother methodTry using this equation:
Mass of product IN GRAMMES
Mass of reactant IN GRAMMES
Mr of product
Mr of reactant
Q. When water is electrolysed it breaks down into hydrogen and oxygen:
2H2O 2H2 + O2
What mass of hydrogen is produced by the electrolysis of 6g of water?Mass of product IN GRAMMES
6g
4
36
So mass of product = (4/36) x 6g = 0.66g of hydrogen
19/04/23Problems with this Problems with this techniquetechnique
Calculating the amount of a product may not always give you a reliable answer...
1) The reaction may not have completely _______
2) The reaction may have been _______
3) Some of the product may have been ____
4) Some of the reactants may have produced other _______
The amount of product that is made is called the “____”. This number can be compared to the maximum theoretical amount as a percentage, called the “percentage yield”.
Words – lost, yield, finished, reversible, products
19/04/23
Atom EconomyAtom Economy
Percentage atom economy =
Relative formula mass of useful product
Total masses of products
Calculate the atom economies of the following:
1) Converting ethanol into ethene (ethene is the useful bit):
C2H5OH C2H4 + H20
2) Making zinc chloride from zinc and hydrochloric acid:
Zn + 2HCl ZnCl2 + H2
19/04/23
Numbers of molesNumbers of molesConsider two liquids:
Now consider two gases:
20cm3 of 0.1mol/dm3 of hydrochloric acid
20cm3 of 0.1mol/dm3 of sodium hydroxide
These two beakers contain the same number of moles
20cm3 of helium at room temperature and pressure
20cm3 of argon at room temperature and pressure
These two gases contain the same number of moles
19/04/23Endothermic and exothermic Endothermic and exothermic reactionsreactions
Step 1: Energy must be SUPPLIED to break bonds:
Step 2: Energy is RELEASED when new bonds are made:
A reaction is EXOTHERMIC if more energy is RELEASED then SUPPLIED. If more energy is SUPPLIED then is
RELEASED then the reaction is ENDOTHERMIC
Energy
Energy
19/04/23
Example reactionsExample reactionsReaction Temp. after
mixing/OCExothermic or endothermic?
Sodium hydroxide + dilute hydrochloric acid
Sodium hydrogencarbonate + citric acid
Copper sulphate + magnesium powder
Sulphuric acid + magnesium ribbon
19/04/23
Reversible ReactionsReversible ReactionsSome chemical reactions are reversible. In other words, they can go in either direction:
A + B C + D
NH4Cl NH3 + HCl
e.g. Ammonium chloride
Ammonia + hydrogen chloride
If a reaction is EXOTHERMIC in one direction what must it be in the opposite direction?
For example, consider copper sulphate:
Hydrated copper sulphate (blue)
Anhydrous copper sulphate (white)
+ Heat
+ Water
CuSO4 + H2OCuSO4.5H2O
19/04/23
Reversible ReactionsReversible ReactionsWhen a reversible reaction occurs in a CLOSED SYSTEM (i.e. no reactants are added or taken away) an EQUILIBRIUM is achieved – in other words, the reaction goes at the same rate in both directions:
A + B C + D
Endothermic reactions
Increased temperature:
Decreased temperature:
A + B C + D
A + B C + D
More products
Less products
Exothermic reactions
Increased temperature:
Decreased temperature:
A + B C + D
Less products
More products
A + B C + D
19/04/23
Making AmmoniaMaking Ammonia
Nitrogen + hydrogen Ammonia N2 + 3H2 2NH3
•High pressure
•450O C
•Iron catalystRecycled H2 and N2
Nitrogen
Hydrogen
Mixture of NH3, H2 and N2. This is cooled causing NH3 to liquefy.
Fritz Haber, 1868-1934
Guten Tag. My name is Fritz Haber and I won the Nobel Prize for chemistry. I am going to tell you
how to use a reversible reaction to produce ammonia, a very important chemical. This is called
the Haber Process.
To produce ammonia from nitrogen and hydrogen you have to use three conditions:
19/04/23Haber Process: The Haber Process: The economicseconomicsA while ago we looked at reversible reactions:
A + B C + D
Endothermic, increased temperature
A + B C + D
Exothermic, increase temperature
ExothermicEndothermic
1) If temperature was DECREASED the amount of ammonia formed would __________...
2) However, if temperature was INCREASED the rate of reaction in both directions would ________ causing the ammonia to form faster
3) If pressure was INCREASED the amount of ammonia formed would INCREASE because there are less molecules on the right hand side of the equation
Nitrogen + hydrogen Ammonia
N2 + 3H2 2NH3
19/04/23
Haber Process SummaryHaber Process Summary
•200 atm pressure
•450O C
•Iron catalyst
Recycled H2 and N2
Nitrogen
Hydrogen
Mixture of NH3, H2 and N2. This is cooled causing NH3 to liquefy.
To compromise all of these factors, these conditions are used:
A low temperature increases the yield of ammonia but is too slow
A high temperature improves the rate of reaction but decreases the yield too much
A high pressure increases the yield of ammonia but costs a lot of money
19/04/23
Rates of ReactionRates of Reaction
Hi. I’m Mike Marble. I’m about to have some acid poured onto me. Let’s see what happens…
Here comes an acid particle…
It missed!
Here comes another one. Look
at how slow it’s going…
No effect! It didn’t have enough
energy!
Oh no! Here comes another one and it’s got more energy…
19/04/23
Rates of ReactionRates of ReactionChemical reactions occur when different atoms or molecules _____ with enough energy (the “________ Energy):
Basically, the more collisions we get the _______ the reaction goes. The rate at which the reaction happens depends on four things:
1) The _______ of the reactants,
2) Their concentration
3) Their surface area
4) Whether or not a _______ is used
Words – activation, quicker, catalyst, temperature, collide
19/04/23
CatalystsCatalystsTask
Research and find out about two uses of catalysts in industry, including:
1) Why they are used
2) The disadvantages of each catalyst
19/04/23
Catalyst SummaryCatalyst SummaryCatalysts are used to ____ __ a reaction to increase the rate at which a product is made or to make a process ________. They are not normally ___ __ in a reaction and they are reaction-specific (i.e. different reactions need _________ catalysts).
Words – different, speed up, used up, cheaper
19/04/23
Rate of reaction graph v1Rate of reaction graph v1
Time taken for reaction to complete
Temperature/ concentration
Reaction takes a long time
here
Reaction is quicker
here
19/04/23
Rate of reaction graph v2Rate of reaction graph v2Amount of product formed/ amount of reactant used up
Time
Slower reactionFast rate
of reaction here
Slower rate of reaction here due to reactants being used
up
Rate of reaction = amount of product formed/reactant used up
time
19/04/23ElectrolysisElectrolysis
++++
----
Positive electrode
Cu2+
Cu2+
Cu2+
Negative electrode
Cl-
Cl-
Cl-
Solution containing copper and
chloride ions
19/04/23
ElectrolysisElectrolysisElectrolysis is used to separate a metal from its compound.
= chloride ion
= copper ion
When we electrolysed copper chloride the _____ chloride ions moved to
the ______ electrode and the ______ copper ions moved to the ______
electrode – OPPOSITES ATTRACT!!!
19/04/23Electrolysis equationsElectrolysis equationsWe need to be able to write “half equations” to show what happens during electrolysis (e.g. for copper chloride):
2 2
2
At the negative electrode the positive ions GAIN electrons to
become neutral copper ATOMS. The half equation is:
Cu2+ + e- Cu
At the positive electrode the negative ions LOSE electrons to
become neutral chlorine MOLECULES. The half equation is:
Cl- - e- Cl2
19/04/23
Purifying CopperPurifying Copper
++++
----
Solution containing copper ions
Impure copper
Cu2+
Cu2+
Cu2+
Pure copper
At the positive electrode:
Cu(s) Cu2+(aq) + 2e-
At the negative electrode:
Cu2+(aq) + 2e- Cu(s)
19/04/23
Electrolysis of brineElectrolysis of brine
Positive electrode
Negative electrode
Sodium chloride (brine)
NaCl(aq)
Sodium hydroxide (NaOH(aq))
Sodium chloride (salt) is made of an alkali metal and a halogen. When it’s dissolved we call the solution “brine”, and we can electrolyse it to produce 3 things…
Chlorine gas (Cl2) Hydrogen gas (H2)
19/04/23Universal Indicator and the pH Universal Indicator and the pH scalescale
Strong acid Strong alkali
Neutral
1 2 3 4 5 6 7 8 9 10 11 12 13 14
Universal Indicator is a mixture of liquids that will produce a range of colours to show how strong the acid or alkali is:
Stomach acid
Lemon juice
Water Soap Oven cleaner
Baking powder
An acid contains hydrogen ions, H+
An alkali contains hydroxide ions, OH-
19/04/23Neutralisation reactionsNeutralisation reactionsWhen acids and alkalis react together they will NEUTRALISE each other:
OHNa
Sodium hydroxide
ClH
Hydrochloric acid
The sodium “replaces” the hydrogen from HCl
ClNa
Sodium chloride
H2O
Water
General equation: H+(aq) + OH-
(aq) H2O(l)
19/04/23
Making saltsMaking saltsWhenever an acid and alkali neutralise each other we are left with a salt, like a chloride or a sulphate. Complete the following table:
Hydrochloric acid
Sulphuric acid Nitric acid
Sodium hydroxide
Sodium chloride + water
Potassium hydroxide
Potassium sulphate + water
Calcium hydroxide
Calcium nitrate + water
19/04/23
Making SaltsMaking SaltsSoluble salts can be made from acids by reacting them with:1) Metals, e.g.
Zn + 2HCl ZnCl2 + H2
2) Insoluble bases, e.g.
CuO + 2HCl CuCl2 + H20
3) Alkalis (alkali = a “soluble base”), e.g.
NaOH + HCl NaCl + H20Salts can be made from these solutions by crystallizing
them.
19/04/23
Ammonium saltsAmmonium salts
Guten tag again. When ammonia dissolves in water it produces an
alkaline solution:
NH3 + H20 NH4OH
This solution can be used to make fertilisers. Very useful!
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