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Pure chemistry - Coggle Diagram
Pure chemistry
Chapter 4: Chemical Bonding & Chapter 5: Structures and Properties of Materials
Noble gases
Characteristic
They are monoatomic (They exist as single atom)
They are chemically unreactive
Electronic configuration
Full valence shell of electrons
Having duplet electronic confguration
Having octet electronic configuration
Other atoms (not full valence shell of electrons)
Chemically combine in three ways to reach full valence shells of electrons
Loss of electrons
Gain of electrons
Different types of ions
Positive ions (cations)
Ions that have a
net positive charge
and usually have a noble gas configuration
Formed when an atom loses one or more electrons
Metal atom tends to lose electron and form positive ions
Examples
Charge of ions: +1
Hydrogen
Sodium
Potassium
Silver
Ammonium
Charge of ions: +2
Magnesium
Calcium
Barium
Iron (II)
Copper (II)
Zinc
Lead (II)
Charge of ions: +3
Iron (III)
Aluminium
Negative ions (anions)
Formed when an atom gains one or more electrons
Most non-metal atoms will gain electrons and form negative ions
Ions that have a
net negative charge
and usually have a noble gas configuration
Examples
Charge of ions: -1
Fluoride
Chloride
Brromide
Iodide
Hydroxide
Nitrate
Manganate (VII)
Charge of ions: -2
Oxide
Carbonate
Sulfate
Charge of ions: -3
Phosphate
Ionic Bonding
Techniques to answer qns in exam
[Compound/Element] has a
giant ionic crystal lattice structure
and
strong electrostatic forces of attractions
between [cations] and [anions].
Defintion
An
ionic bond
is the mutual electrostatic forces of attraction between ions of opposite charges
Properties
Structure
Giant ionic crystal lattice structure
Attraction
Strong electrostatic forces of attraction between [cations] and [anions]
Melting and boiling point
Very high
Large amount of energy is required to overcome the strong electrostatic forces of attraction between
[ions of opposite charge]
Hardness
Hard but brittle
Solubility
Soluble in water
Insoluble in organic solvent
Electrical conductivity
Only in molten/liquid or aquaeous state [presence of mobile ions]
Sharing of electrons
Covalent bonding
Definition
A
covalent bond
happens when atoms are
sharing electrons
to reach full valence shell of electrons
Types of covalent bonding
Simple covalent bond
Characteristics
Simple covalent molecules have a countable number of atoms in fixed ratios
Techniques to answer the qns
[Compound] has a
simple covalent structure
with
strong covalent bonds
betwween [cation] and [anion] and
weak intermolecular forces of attraction
Properties
Structure
1 more item...
Attraction
2 more items...
Melting and boiling point
1 more item...
Solubility
2 more items...
Electrical conductivity
1 more item...
Giant covalent bond
Characteristics
Giant covalent molecules have an uncountable number of atoms in fixed ratios.
Techniques to answer the qns
[Compound] has a
giant covalent structure
with
strong covalent bonds
between atoms and
weak intermolecular forces of attraction
Properties
Structure
2 more items...
Hardness
2 more items...
Melting and boiling point
1 more item...
Solubility
2 more items...
Electrical Conductivity
2 more items...
Macromolecules
Characteristics
A macromolecule consist of many covalent molecules joined together into chains of much larger molecules
Having different combinations of atoms, meaning that the properties vary due to the combinations of atoms
Examples of macromolecules
Natural
4 more items...
Man-made (Chemistry)
4 more items...
Biology
4 more items...
Properties
Structural Properties
2 more items...
Melting and boiling points
2 more items...
Solubility
2 more items...
Electrical conductivity
1 more item...
Between positively charged ions
Metallic bond
Structure
Giant metallic structure
held by positively charged ions in a "sea of delocalised electrons"
Definition
Mutual electrostatic forces of attractions between
positively charged ions
and the "
sea of delocalised electrons
"
Elements
What is it made of?
Only one element
How is it formed?
Mostly naturally occurring
Melting and boiling points
Fixed
Can appear as
Atoms, if not chemically combined
Molecules, if covalently bonded
Lattice of positive ions with sea of delocalised electrons
Compound
What is it made of?
Two or more elements that are chemically combined
How is it formed?
From a chemical reaction
What is the ratio of its constituents?
Fixed ratio
What are its properties like?
Has different properties from its constituent elements
Melting and boiling points
Fixed
Separating compound in two ways
Thermal decomposition: Exposing the compound to strong heat
Electrolysis: Passing electric current through the compound
Mixture
What is it made of?
Two or more elements and/or compounds that are not chemically combined
How is it formed?
Usually from physical mixing
What is the ratio of its constituent?
no fixed ratio
What are its properties like?
Usually has similar properties to its constituent substances
Melting and boiling points
Melt or boil over a range of temperatures
Metals and alloys
Metals
Structural Properties
Regular lattice arrangement
Malleable
Ductile
Reasons
When little amount of force is applied, the layer of atoms will slide over one another easily
Properties
Melting and boiling points
Very high melting and boiling point
Atoms are held together in a lattice by strong metallic bonds
Heat conductivity
Good conductor of heat
Delocalised valence electrons allow efficient transfer of thermal energy throughout the giant metallic lattice
Electrical conductivity
Good conductor of electricity
Alloys
Definition
Mixture of a metal with one or other elements
Structures
Irregular lattice structure
Reasons
Atoms are of different sizes, hence the regular lattice arrangement are disrupted
Properties
Ability to stretch
Less malleable
Larger force is needed to make the layers slide over one another
Less ductile
Melting and boiling point
Melts or boils over a range of temperatures
Alloys are mixtures of two or more elements
Heat conductivity
Good conductor of heat
Delocalised valence electrons allow efficient transfer of thermal energy throughout the giant metallic lattice
Electrical conductivity
Good conductor of electricity
Reasons
"Sea of delocalised electrons" observed in the metals and alloys
Chapter 3: Atomic Structure
Atoms
Three main sub-atomic particles in nucleus
Neutrons
No electrical charge
Electrons
Relative mass: 1/1840
Situated at the electron shell
Negative electrical charge (-1)
Protons
Relative mass: 1
Situated in the nucleus of the atom
Positive electrical charge (+1)
Something to take note
Identity of the elements is defined based on the no. of protons
Nucleons
is the sub-atomic particles in the nucleus, also known as
mass number
Proton number is the no. of protons in the nucleus
Characteristics
Electrically neutral (means that no. of protons = no. of electrons)
Smallest particle
that can still have the chemical characteristics of an element
Ways to express details
Nuclide notation
Methods to express
A (nucleon number) written as superscript
Z (Proton number) written as subscript
X (Atomic symbol) written as per usual
Ions
Characteristics
Formed when an atom of groups of atoms gains or loses electron(s), but the number of protons and neutrons remains the same.
The charge number needs to be written as superscript after writing the atomic symbol
Cations and anions
Cations is ions that is positively charged like Al^3+
Anions is ions that are negatively charged like O^2-
Metal atoms loses valence electrons to form cations
Non-metals gains valence electrons to form anions.
Isotopes
Characteristics
Are atoms of the same element with same proton number but different nucleon number, meaning that they have different number of neutrons
examples
Hydrogen-1 (0 neutron)
Hydrogen-2 (1 neutron)
Hydrogen-3 (2 neutrons)
How are electrons arranged in the atoms
Electron shells and energy levels
Innermost shell (closest to the nucleus) --> Lowest energy
Outermost shell (Furthest from the nucleus) --> Highest energy
Electron shells and electrons
There are 3 layers of electron shells
The outermost shell is known as valence electron shells
First electron shell can hold a
maximum
of
2 electrons
Second and third electron shells can hold a
maximum
of
8 electrons
Electronic configuration
Electronic configuration is the way to express the number of electrons in an atoms and how they are arranged according to their electron shells.
Examples
Lithium (Li): 2,1
Oxygen (O): 2,6
Calcium (Ca): 2,8,8,2
Chlorine: 2,8,7
Chapter 8: Acid and Bases
Acids
Definition
An acid is a substance that produces hydrogen ions, H+, in aqueous solution.
Properties of acids
Sour Taste
Produce H+ ions when dissolved in water, resulting aqueous solution to be able to conduct electricity
Turns blue litmus paper red
Reacts with reactive metals
General Formula: Acid + Metals --> Salt + Hydrogen
Salts formed under different acid
Sulfates when formed from sulfuric acid
Nitrates when formed from nitric acid
Chlorides when formed from hydrochloric acid
Ways to check
We can test for hydrogen gas by placing a burning splint at the mouth of the test tube. Hydrogen gas extinguishes the burning splint with a “pop” sound.
Reacts with bases
General Formula: Acid + Bases --> Salt + Water
Reacts with carbonates
General Formula: Acid + Carbonate --> Salt + Water + Carbonate
Ways to check
We can test for carbon dioxide gas by bubbling the gas through limewater. Carbon dioxide gas forms a white precipitate with limewater.
Strength
Defintion of strength
the extent of ionisation of an acid, when dissolved in water
Strong acid
an acid that completely ionised in aqueous solutions
Weak acid
an acid that only partially ionised in aqueous solutions.
Bases
Definition
A base is any metal oxide or hydroxide that contains either the oxide ions (O2-) or the hydroxide ions (OH-).
Soluble bases = Alkalis
Strength
Strong alkalis
Fully ionised in water to when dissolved in water to produce OH- ions
Weak alkalis
Partially ionised in water to when dissolved in water to produce OH- ions
Properties of alkalis
Bitter taste
Feels soapy and slippery
Dissolves in water to form solutions that conduct electricity
Turns red litmus paper blue
Reacts with acids
General Equation: Acid + Alkali --> Salt + Water
Ionic Equation for neutralisation: H+ (aq) + OH- (aq) --> H2O (l)
Reacts with ammonium salts
General Equation: alkali + ammonium salt → salt + water + ammonia
Ways to check
We can test for ammonia gas with a piece of damp red litmus paper. Ammonia gas turns the damp red litmus paper blue.
Oxides
Comparing pH levels of the solutions
Instruments used
Universal Indicators
Methyl Orange
Screened methyl orange
Litmus
Thymolphthalein
Chapter 1: Experimental Chemistry
measures
Physical quantities
such as
measurement of time
Common Unit
SI unit: Second (s)
Minute (min)
Hour (h)
Conversion of units
1 min = 60s
1h = 60min = 3600s
Instruments used to measure and their degree of accuracy
Digital Stopwatch (+/- 0.01s)
Analogue Stopwatch (+/- 0.1s)
Measurement of temperature
Common unit
SI unit: Kelvin (K)
Degree Celsius (°C)
Degree Fahrenheit (°F)
Instruments used
Alcohol Thermometer
It shows a range of temperatures from -10°C - 110°C
Digital Thermometer
Oral Digital Thermometer
Conversion to be take down as
notes
Temperature in K = Temperature in °C + 273
Measurement of Length
Common unit
SI unit: Metre (m)
Milimetre (mm)
Centimetre (cm)
Decimetre (dm)
Kilometre (km)
Conversion
1m = 10dm
1dm = 10cm
1cm = 10mm
Instruments used and their degree of accuracy
Metre rule (+/- 0.1cm)
Measuring tape (+/- 0.5cm)
Measurement of Mass
Common unit
SI unit: Kilogram (kg)
Gram (g)
Miligram (mg)
Tonnes (t)
Kilotonnes (kt)
Conversion
1kg = 1000g = 1000000mg
1t = 1000kg = 1000000g
1kt = 1000t = 1000000kg
Instrument used and their degree of accuracy
Electronic balance (+/- 0.01g)
Measurement of Volume
Common unit
SI unit: Cubic Metre (m^3)
Cubic Decimetre (dm^3)
Cubic Centimetre (cm^3)
Cubic Kilometre (km^3)
Apparatus used and their degree of accuracy
Pipette (Measures accurate fixed volumes, e.g. 10.0cm^3 / 25.0cm^3)
Volumetric Flask (Measures Accurate fixed volumes that are larger than pipette, e.g. 100cm^3 / 250cm^3)
Measuring cylinder (Measures a range of volumes to the nearest 0.5cm^3)
Burette (Measures a range of volumes to the nearest 0.05cm^3
Methods for
Collecting gases
Water displacement
Properties of gases
Solubility
Insoluble to slightly soluble
Density
No effects with changes of density
Examples
Hydrogen
Oxygen
Carbon Dioxide
Downward delivery
Properties of gases
Solubility
Can be soluble or insoluble
Density
denser than air
Examples
Chlorine
Hydrogen chloride
Sulfur dioxide
Upward delivery
Properties of gases
Density
Less dense than air
Examples
Ammonia
Drying gases
Concentrated sulfuric acid
Examples
Most gases, including chlorine and hydrogen chloride
Notes
Not suitable for gases reacting with sulfuric acid
Quicklime (Calcium Oxide)
Examples
Ammonia
Notes
Calcium oxide absorbs moistures and carbon dioxide from the air, so it must be freshly heated before use. This method cannot be used to dry gases reacting with calcium oxide
Fused Calcium Chloride
Examples
Hydrogen
Nitrogen
Carbon Dioxide
Notes
Calcium Chloride readily absorbs moisture from the air, so it must be freshly heated before use. This method cannot be used to dry gases which react with calcium chloride.
Separating mixture
Solid-Solid
Magnetic Attraction
Separating magnetic solids from non-magnetic solids
Examples of magnetic materials are iron. cobalt, nickel and some alloys
Sieving
A sieve can be used to separate solids with different particle sizes
Using suitable solvents
A suitable solvent can be used to separate solid-solid mixtures in which only one of the solids is soluble in the solvent.
Liquids that dissolves solids are known as
solvents
The solids that dissolves in the solvent are called
solute
The ability of a solute to dissolve in a solvent is known as its
solubility
Sublimation
Sublimation can be used to separatee a substancee that changes from the solid to gaseous state directly.
Common substances undergo sublimation: Iodine, Naphthalene used in mothballs, dry ice
Solid-Liquid
Filtration
Filtration can be used to separate
insoluble solids
from liquids
The liquid that passes through the filter paper is called the
filtrate
The solid that remains on the filter paper is known as the
residue
Evaporation to dryness
Evaporation to dryness is used to separate a dissolved solid from its solvents by heating the mixture until all the solvent has vapourised
Examples: Salt-water solution
Crystallisation
Crystallisation iis used to obtain a pure solid from its saturated solution
A
saturated solution
is one in which no more solute can be dissolved
Simple distillation
Simple distillation is used to separate a pure solvent (liquid) from a solution
Relies on solid and liquid components in a mixtures having different boiling points
Liquid-Liquid
Separating funnel
A separating funnel is used to separate
immiscible
liquids
Chromatography
Chromatography is used to
separate a mixture of substances
which have
different solubilities
Chromatograms show the separated substances on the paper after chromatography
Rf value = Distance Travelled by the substance/ Distance travelled by the solvent
Identifying colourless substances
To identify colourless substances on the chromatograms,
locating agents
is introduced.
locating agents is chemical that reacts with colourless substances
To identify colourless substances on the chromatograms,
Ultraviolet (UV)
light is introduced
Applications
Identify unauthorised substances like pesticides and poisons in food
Detect small quantities of banned substances in an athlete's urine or blood sample
Separate components like DNA fragments in samples for forensic investigations
Fractional Distillation
Fractional distillation is used to separate
miscible liquids
with
different boiling points
examples
Ethanol-water mixture
Industrial applications
Oil refineries separate different substances from crude oil, which are further processed into useful chemicals like petrol, kerosene and lubricating oils
Liquefied air is separated to produce nitrogen, oxygen and argon gas for industrial applications
Ethanol produced by glucose fermentation is extracted in breweries
Determining purity of substances
Pure substance has a
specific/fixed/constant
melting or boiling point under fixed conditions
Mixtures melt or boil over a range of temperatures
Important terms to remember
Miscible
meaning
Describe liquids that form a uniform (
homogeneous
) solution when mixed together
Immiscible
meaning
Describe liquid that cannot mix together to form a single liquid (
heterogenous solution
).
example
Water and oil components of curry
Chapter 2: Kinetic Particle Theory
Kinetic Particle Theory
states that all matter is made up of tiny particles and these particles are in constant random motion.
Solid
Particle arrangement
Very closely packed
Orderly manner
Very strong forces of attraction
Movement
Vibrate or rotate only about their fixed positions
possessing very low kinetic energy
Liquid
Particle arrangement
Closely packed
Disorderly manner
Strong forces of attraction
Movement
Slide past one another freely throughout the liquid
Possessing low kinetic energy
Gas
Particle arrangement
Very far apart
Disorderly manner
Weak forces of attraction
Movement
Move quickly & randomly in any directions
possessing very high kinetic energy
Changes of state (heating and cooling curve are to be seen on the notes)
Heating
Melting
Before melting (heating to melting point of the substances)
Thermal energy is converted to kinetic energy of the particles
Particles vibrate and rotate faster about their fixed positions
Temperature rises towards the melting point of the substances
During melting (solid is melted to form liquid)
Thermal energy is absorbed from the surroundings and the temperature of the solid is at its
melting point
Particles with increased energy can overcome the forces of attraction in the solid state.
The orderly packing arrangement of the particles is disrupted.
Both solid and liquid are present during the melting process
The temperature remains constant throughout the melting process until all the substances have melted
After melting (Continuous heating beyond the melting point)
After all the solid substances has melted, thermal energy is again converted to kinetic energy of the particles.
The particles can move freely throughout the liquid
Temperature of the liquid rises beyond the melting point of the substances
Evaporation or boiling
Before evaporation or boling (heating to the boiling point of the substances)
Thermal energy is converted to the kinetic energy of the particles
Particles slide past one another with increasing speed
Temperature of the liquid rises towards the boiling point of the substances
During evaporation or boiling (liquid is evaporated or boiled to form gas)
Thermal energy is absorbed from the surroundings and the temperature of the liquid is at its boiling point
Particles with increased energy can overcome the forces of attraction in liquid state.
The particles move further apart, quickly and randomly
Both liquid and gas are present during the boiling process
Temperature remains constant throughout the boiling process until all liquid substances has boiled or evaporated
After evaporation or boiling (heating beyond the boiling point of the substance)
After all the liquid has boiled off/ evaporated, thermal energy is again converted to kinetic energy of the particles
Particles can move quickly and randomly in any direction
Temperature of the gas rises beyond the boiling point of the substance
Sublimation
Thermal energy from the surrounding is transferred to the solid, resulting in the substance converting from a solid to a gas
Temperature remains constant until all the substancee is in the gaseous state
Cooling
freezing
Before freezing (cooling to the freezing point of the substances)
Kinetic energy of the particles is converted to thermal energy, which is transferred to the surroundings
With less kinetic energy, the particles slow down
The temperature of the liquid reduces towards the freezing point of the substances
During freezing (liquid is freeze to form solid)
The particles loses energy to the surroundings and the temperature is at the
freezing point
The particles with less energy are drawn closer together by the forces of attraction between them.
The particle arrangement becomes more orderly
Both solid and liquid are present during the freezing process
Temperature remains constant throughout the freezing process until all the liquid substances has solidfied
After freezing (cooling beyond the freezing point)
After all the liquid has solidified, kinetic energy of the particles is again converted to thermal energy and transferred to the surroundings
Particles can viibrate and rotate onlly about their fixed positions
The temperature of the solid reduces beyond the freezing point of the substances
Condensation
Before condensation (cooling to the condensation point of the substances)
Kinetic energy of the particles is converted to thermal energy, which is transferred to the surroundings
With less kinetic energy, the particles slow down
Temperature of the gas reduces to the condensation point of the substance
During condensation (gas is condensed to form liquid)
The particles lose energy to the surroundings and the temperature is at the condensation point.
The particles with less energy are drawn closer together by the forces of attraction between them
The arrangement of the particles become less disorderly
Both gas and liquid are present during the condensation process
The temperature remains constant throughout the condensation process until all the substances has condensed
After condensation (cooling beyond the condensation point of the substance)
After all the gas has condensed, kinetic energy of the particles is again converted to thermal energy and transferred to the surroundings
Particles can slide past each other freely throughout the liquid only
Temperature of the liquid cools beyond the condensation point of the substances
Vapour deposition
Particles in the gas are cooled until they slow down and arrange themselves directly into the solid state.
Diffusion
is the net movemet of particles from a region of higher concentration to a region of lower concentration
Practical Example
In liquid (tea)
The particles of tea move away from the bag, towards the regions in the liquid that have lower concentrations of tea
Eventually, the concentration of the tea becomes the same throughout the cup
When a tea bag is placed in a glass of water, the particles of the tea diffuse out of the bag and into the water
In gas (perfume)
When liquid perfume is sprayed out of the bottle, the more
volatile
substances vapourise almost immediately. The other substances fall as liquids onto the surface of the skin
The perfume vapours diffuse away from the bottle, through the air and eventually into our noses. At higher temperatures, the vapours diffuse faster and we can detect the fragance more quickly
Conditions affecting the rate of diffusion
Temperature
With higher temperatures, particles have more kinetic energy to move. With more kinetic energy, the particles can move faster hence diffuse faster.
With lower temperatures, particles have less kinetic energy to move. With less kinetic energy, the particles move slower hence diffuse longer
Particle Mass
Particles with greater mass requires more kinetic energy to move at a given speed.
Chapter 6: Chemical Formulae and Equations
Chemical formulae
What is it?
a recipe that shows the ratio of elements that are combined in one unit of substance.
Consists of
Chemical symbol(s) that indicate the element(s) present
Subscript(s) indicating the number of atoms of each element present.
Types of elements involved
Monoatomic
Elements that exists as uncombined atoms
Examples
Elements in group 18
Argon
Neon
Reasons
Generally unreactive
Full valence shells of electrons
Diatomic
molecules that exists as two chemically combined atoms.
Examples
Hydrogen: H2
Oxygen: O2
Nitrogen: N2
Fluorine: F2
Chlorine: Cl2
Bromine: Br2
Iodine: I2
Polyatomic
molecules that exists as three or more chemically combined atoms.
Examples
Sulfur: S8
Phosphorus: P4
Ozone: O3
Compounds
Characteristics
Made up of atoms of elements that are chemically combined.
Have fixed formulae
Examples
Ammonia
Chemical formula
NH3
Atoms present
1 nitrogen
3 hydrogen
Copper (II) Sulfate
Chemical Formula
CuSO4
Atoms present
1 copper
1 sulfur
4 oxygen
Sodium Hydroxide
Chemical Formula
NaOH
Atoms present
1 sodium
1 oxygen
1 hydrogen
Hydrochloric Acid
Chemical formula
HCl
Atoms present
1 Hydrogen
1 Chlorine
Ethanoic Acid
Chemical Formula
CH3COOH
Atoms present
4 Hydrogen
2 Carbon
2 Oxygen
Deducing chemical formulae
Ways to deduce chemical formulae of compounds
Cross-multiplying
How to use it?
Cross multiply the valences of the chemical species
Things to take note
Simplify the ratio if applicable
Deducing charges of ions from chemical formulae
Ways to do it
Look for the charges of the individual ions
Step 1: Get the overall charges = 0
Step 2: Look for the individual charges of the ions that we know.
Step 3: Get the individual charges we want as
x
Step 4: Solve for
x
and we get the charges of the ions
Determining whether it is positively charged or negatively charged
Metal ions: Positively charged
Non-metal ions: Negatively charged
Transition metals: Based on scenario
Valency
What is it?
Valency of an
element
refers to the
number of electrons gained, lost or shared
in order for the element to
obtain a stable, noble gas configuration.
Valency of an
ion
is its
charge without the sign
How to determine?
Group numbers
Follows a predictable pattern across the periodic table
Examples
Group no. 1
Lithium
Valency: 1
Sodium
Potassium
Group no. 2
Beryllium
Valency: 2
Magnesium
Calcium
Roman numerals
Transition metals can form more than 1 stable ions, hence valences are indicated in the brackets
Examples
Iron (III) : Valency is 3
Iron (II): Valency is 2
Copper (II): Valency is 2
Copper (I): Valency is 1
Titanium (IV): Valency is 4
Polyatomic ions
Made up of more than one atom covalently bonded together. They carry overall charges and overall valences is the charge on the ions
Examples
Ammonium: NH4+
Valency is 1
Hydroxide: OH-
Nitrate: NO3-
Sulfate: SO4^2-
Valency is 2
Carbonate: CO3^2-
Phosphate: PO4^3-
Valency is 3
Different kinds of equations
Word equation
Characteristics
Chemical names of the reactants and products are used.
Ways to written down the equation
Reactants on the left hand side of the equation
Products on the right hand side of the equation
Examples
Sodium + Chlorine --> Sodium Chloride
Hydrochloric Acid + Sodium Hydroxide --> Sodium Chlorine + Water
Chemical Equations
Examples
Characteristics
Chemical formulas of the reactants and products are used.
Steps to balance it
Writing chemical formulae: Write the chemical formulae of the reactants and products in an unbalanced chemical equation.
Number listing: List the number of each atom present. If the numbers on each side of the equation do not balance, proceed to step 3.
Add molecules without changes: Add molecule(s) of the unbalanced species to balance the equation. Do not change the chemical formulae or subtract atoms.
Include state symbols: Add the state symbols into the balanced chemical equation
Ionic Equatons
Examples
Characteristics
spectator ions are removed from the ionic equation.
shows the ions that took part in the reaction.
Steps to construct it
Construct chemical equation: Construct a balanced chemical equation with state symbols.
Split the couple: Split substances in the aqueous state into their constituent ions.
Break the couple: Cancel out the ions that appear on both sides of the equation that have the same charge and physical state.
Leave the rest: What remained is the ionic equations
