Chemistry finisher

Chapter 1. The Nature of Chemistry
Key Concepts
 Chemistry - is the study of matter and
the changes it undergoes. It is
sometimes called the central science
because it overlaps with many other
sciences.
 Technology - is the application of
science. It has improved the quality of
human life.
 SI units - are used to express physical
quantities in all sciences. Metric prefixes
are used to make units smaller or larger.

 Precision - is how close several
measurements are to the same value.
 Accuracy - tells how close a
measurement is to the true or
accepted digit.
 Significant - figures include both the
certain digits and the estimated digit.
 Scientific notation - is used to write
very small or very large numbers.

 Dimensional analysis - is the
technique that uses conversion
factors. The guide to ensure that
conversion factor are properly
formulated is the cancellation of
units.

Chapter 2. Matter: Its Composition
and Organization. Key Concepts
 Matter - is anything that has mass
and volume. Properties of matter
differ for solids, liquids, and gases.
 A pure substance is either an element
or a compound. An element is a
substance that cannot be broken down
to simpler substances. A compound is
formed when two or more elements
combine in a chemical change.

 A change in the properties of substance without a
change in composition is a physical change. If
there is a change in the composition of a
substance, a chemical change has occurred.
Chemical changes produce matter with new
properties.
 The physical combination of two or more
substances is a mixture. A mixture has a variable
composition. It may be heterogeneous or
homogeneous. Heterogeneous mixtures (coarse
mixtures, suspensions, and colloids) do not have
uniform properties throughout, while
homogeneous mixtures (solutions) have uniform
properties.

 Solutions may be gases, liquids, or solids.
 The components of a mixture can be
separate by physical methods.
 Colloids - are mixtures of two or more
solids, liquids, or gases whose particles
are bigger than the particles of a
solution but smaller than those of a
suspension.
 Tyndall effect, Brownian
movement, adsorption, and electrical
charge are the properties of colloids.

 Colloids are prepared and purified by
condensation and dispersion methods.
 Condensation - is the process of
combining molecules to form colloidal
particles.
 Dispersion - is the process of breaking
down large particles to colloidal size.
 Energy - is the capacity to do work or to
transfer heat. It is involved whenever
matter undergoes a change.

Chapter 3. Atomic Theory.
Key Concepts
 Over 2400 years ago, the concept of the
atom was proposed by Greek
philosophers.
 In the early 19th century, Daltons
proposed the atomic theory. This theory
is related to the three fundamental laws
of matter.
 (1) The total mass of the reactants and
products are constant during a chemical
reaction (law of conservation of mass).

 (2) Any sample of compound, has
elements in the same proportion (law
of definite composition).
 (3) In different compounds of
the same elements, the mass of one
element that combines with a fixed
mass of the other can be expressed
as a ratio of small whole numbers (law
of multiple proportions).

 Thomson’s experiment on the behavior of
cathode rays in magnetic and electric
field led to the discovery of the electron
and the measurement of its charge to
mass ratio.
 Millikan’s oil drop experiment measured
the charge of the electron.
 Becquerel and the Curies discovered
radioactivity.
 Rutherford’s studies on alpha rays led to
the discovery of nucleus.

 Atoms have a nucleus that contains protons
and neutrons. Electrons move in the space
around the nucleus.
 Elements can be classified by atomic
number or the number of protons in the
nucleus of an atom.
 All atoms of a given element have the same
atomic number. The mass number of an
atom is the number of protons and neutrons.
 All atoms of the same element that differ
in mass number are known as isotopes.

Chapter 4. Electronic Configuration.
Key Concepts
 The properties of visible light and other
forms of electromagnetic radiation led to
the electronic structure of atoms.
 Max Planck proposed that energy is
absorbed and emitted in discrete amounts
or individual packets called quanta (plural
for quantum).
 Albert Einstein used Planck’s theory to
explain the photoelectric effect. He
proposed that light consists of quanta of
energy which behave like tiny particles of
light. He called these energy quanta
photons.

 The concept of quantized electrons grew
from the study of line spectra of atoms. A
line spectrum consists of quanta of energy
which can be used like fingerprints to
identify the element.
 Niels Bohr used the line spectra to explain
specific energy levels within the atom. He
proposed the planetary model of the atom.
 Louis de Broglie discovered the wave nature
of matter which initiated the development
of a new mathematical description of
electron configuration.

 Heisenberg’s uncertainty principle explained the
impossibility of simultaneously measuring the
momentum and location of an electron.
 Erwin Schrodinger devised the quantum
mechanical model of the atom which described
electrons as waves that exist in quantized energy
levels.
 The regions in space around the nucleus where
electrons are most likely to be found are called
orbitals. These orbitals have various shapes and
are labeled s, p, d, and f. Each principal energy
level or shell consists of these orbitals.

 The manner in which electrons are arranged
around the nucleus of an atom is called electron
configuration.
 The Aufbau principle, the Puali exclusion
principle, and the Hund’s rule are applied in
writing electron configurations.
 The Aufbau principle tells the sequence in which
orbitals are filled.
 The Pauli exclusion principle states that a
maximum if only two electrons can occupy an
orbital.
 Hund’s rule explains that electrons pair up only
after each orbital on a sublevel is occupied by a
single electron.

Chapter 5. The Periodic Table.
Key Concepts
 Different periodic table were developed
by
Dobereiner, Newlands, Mendeleev, and
Meyer. The periodic table was based on
similarities in properties and reactivities
of elements in the increasing order of
their atomic mass.
 Discrepancies in these periodic tables
were resolved when Moseley established
that each element has a unique atomic
number and showed that elements should
be arranged according to their
increasing atomic number.

 The periodic table is organized into 18
groups or families and 7 periods or rows.
The groups are organized further into
s, p, d, and f blocks based on how valence
electrons fill each sublevel. Elements in a
group have similar properties because
they have the same valence electrons.
 Atomic radius decreases from left to
right across a period because the
positive charge of the atoms
increases, which attracts electrons more
strongly.

 Atomic radius increases down a group
because the electrons of the atoms fill
more energy levels.
 Ionization energy - is the energy
absorbed to remove an electron to form
a positive ion.
 Electron affinity - is the energy when
an atom gains an electron forming a
negative ion.
 Electronegativity is the attraction of an
atom for electrons in a chemical bond.

 The trends for ionization
energy, electron affinity, and
electronegativity ate the same. They
increase from left to right of the
periodic table and decrease down a
period.
 Metals are found on the left side of the
periodic table. Nonmetals are found on
the upper right side of the periodic
table. Metalloids have some properties
of metals and nonmetals.

Chapter 6. Chemical Bonds.
Key Concepts
 Chemical bonds are classified into three groups: ions
of opposite charges; covalent bonds, which result from
the sharing of electrons by two atoms; and metallic
bond, which are the attractions among positively
charged ions for delocalized electrons.
 These bonds involve the valence electrons with the
tendency of atoms follow the octet rule. This can be
represented by electron – dot symbols or Lewis
symbols.
 Resonance structures are used when a simple Lewis
structure is not adequate to represent a particular
molecule or ion (specie). Some covalent molecules
formed from atoms of the representation groups
1, 2, and 3 lack octet configurations while atoms from
5, 6, and 7 form expanded octet configurations.

 A polar covalent bond is formed when
electrons are not shared equally between
two atoms.
 Electronegativity difference of bonded
atoms determines the kind of bond
formed between the atoms.
 The sharing of one pair of electrons
produces a single bond, the sharing of
two pairs, a double bond, and three
pairs, a triple bond. Double and triple
bonds are also called multiple bonds.

Chapter 7. Molecular Geometry.
Key Concepts
 The shapes of small molecules can de
explained in terms of the VSEPR model
which states that electron pairs arrange
themselves as far apart as possible to
minimize electrostatic repulsion.
 The geometry of molecules is
determined by the arrangement of
bonding pairs and lone pairs.
 The five common shapes of small
molecules are linear, trigonal
planar, tetrahedral, trigonal
bipyramid, and ictahedral.

 The electron pair cloud repulsion model suggests that
the denser the electron clouds, the greater the
repulsive force. The order from greatest to least
repulsive force is that triple bond > double bond > lone
pair > single bond (≡>═>1.p.>─).
 Molecules that contain polar bonds (bond dipoles) may
be polar or nonpolar molecules, depending on the shape
of the molecules. The properties of polar molecules
(dipole) are different from those of nonpolar
molecules.
 Valence bond theory - is an extension of the Lewis
covalent bond. In this theory, bonds are formed when
neighboring atoms overlap and the potential energy of
the system decreases. The greater the overlap, the
stronger the bond formed.

 Shapes of molecules are also described in terms
of hybrid orbitals. The process of hybridization
involves the promotion of electron to empty
orbital(s) and mixing of the orbitals to form
equivalent numbers of hybrid orbitals. Hybrid
orbitals can overlap with orbitals of other atoms
to make bonds. Or they can accommodate lone
pairs.
 Covalent bonds that overlap end to end along the
line connecting the atoms are called sigma (σ)
bonds. When p orbitals overlap on a side to side
orientation perpendicular to the line connecting
the atoms, these are called pi (π) bonds.

Chapter 8. Chemical Names and Formulas.
Key Concepts
 The charges or oxidation numbers of the ions of
representative elements are determined by their
position in the periodic table.
 Most transition metals have more that one
common ionic or oxidation numbers. A polyatomic
ion is a group of atoms that behaves as an ion –
ide. If cations have more than one ionic charge, a
Roman numeral is used in the name.
 Ternary ionic compounds contain at least one
polyatomic ion. The names of these compounds
end in – ite or – ate.
 Binary molecular compounds are composed of two
nonmetallic elements. Prefixes are used to
indicate the number of atoms each element that
are present in a molecule of the compound.

 Binary acid are compounds that contain hydrogen
and nonmetal ions. They are named by using the
prefix hydro followed by the name of the anion
ending in – ic acid.
 Ternary acid contain hydrogen and polyatomic
ions. They are named by using the name of the
polyatomic ion ending in – ic or - ous acid
 Based are compounds containing a metal ion and
hydroxide ion(OH‾). Bases are named by writing
the name of the cation followed by hydroxide.
 Salts are named by using the name of the cation
followed by the name of the anion.

Chapter 9. Chemical Reactions.
Key Concept
 Chemical reactions are represented by
chemical equations.
 The substances that undergo chemical
changes are the reactants and the
substances formed are the products.
 Chemical equations must be balanced to be
consistent with the law of conservation of
mass. In balancing an equation, appropriate
coefficients are placed before the formulas
of the reactants and products so that the
same number of atoms of each element
appears on each side of the equation.

 The state of a substance in an equation is
detonated by (s), (1), and (g) for
solid, liquid, and gas, respectively. A
substance dissolved in water is denoted by
(aq) for aqueous. If heat, light, or
electricity is used to initiate the
reaction, its process or symbol is written
above the arrow. If a catalyst is used to
increase the speed of reaction, its formula
or symbol is also written above the arrow.
 In a combination reaction, two or more
elements or compounds combine to produce
a single product.

 In a decomposition reaction, a single
compound is broken into two or more simpler
substances.
 In a single replacement reaction, a more
chemically active element displaces a
substance below it in the activity series.
 A double replacement reaction involves the
exchange of cations and anions between two
compounds. Replacement reactions can be
written as net ionic equations.
 In a combustion reaction, oxygen is always
one of the reactants.

Chapter 10. Stoichiometry.
Key Concept
 A mole is the amount of substance that contains
6.02 ×1023 particles or species.
 The representative particles of elements are the
atoms.
 Molecules are representative particles of
molecular compounds and diatomic elements.
 The representative particles for ionic compounds
are formula units. The mass of a mole of
atoms, molecules, or ions is its formula weight
expressed in grams called molar mass.
 A mole is defined in terms of the number of
particles in a substance or the mass in grams of
the substance. The mole can be used in converting
among different units.

 Percent composition of a compound is the
percent by mass of each element in a compound.
 Empirical formula is the simplest whole-number
ratio of atoms of elements in a compound. This
can be calculated from the percent composition
of a compound.
 Molecular formula shows the actual number of
atoms of each element in a compound. It may be
the same as or a multiple of an empirical formula.
 Stoichiometry is the study of the quantitative
relationship of individual compounds in chemical
reactions.

 The coefficients in a balanced equation represent
the relative number of moles of each substance.
Coefficients are used in establishing conversion
factors as mole ratios in solving stoichiometric
problems.
 The conversion factor relates the mole of a given
substance to the moles of the required substance.
Units such as grams and particles are converted
to moles when solving stoichiometric problems.
 When reactants supplied are not in the exact
amounts required by the balanced equation, that
which is used up is the limiting reagent and that
which remains after the reaction is completed is
the excess reagent.

 The theoretical yield is the amount of
product obtained when all of the
limiting reagent is used up.
 The actual yield is the product
formed when the actual reaction is
carried out.
 The percent yield is the ratio of the
actual yield to the theoretical yield
expressed in percent.

Chapter 11. Gases
Key Concept
 The physical properties of gases are given
by four quantities:
 Pressure P
 Volume V
 Temperature T
 Amount of Gases n
 The behavior of gases can be explained by
the kinetic molecular theory.
 The standard temperature and pressure
(STP) is 0°C and 1 atm.
 Atmospheric pressure is the pressure
exerted by the gases (air) around us which
is 1 atm or 760 mm HG.

 Boyle’s law states that the pressure and volume of a gas are
inversely proportional to its absolute temperature (constant n
and T).
 Charles law states that the volume of a gas is directly
proportional to its absolute temperature (constant n and P).
 Avogadro's law states that equal volumes of gases contain the
same number of particles (constant T and P).
 Ideal gas equation PV=nRT is a combination of the gas laws.
 Daltons law states that the pressure of a mixture of gases is
the sum of the partial pressure of the component gases.
 Real gases behave like ideal gases in ordinary conditions except
at high pressure and low temperature.
 Lighter gases diffuse and effuse faster than heavier gases do.

Chapter 12. Liquids and Solids
Key Concept
 At room temperature, substances with
weak intermolecular forces of attraction
are gases; those with moderate
intermolecular forces are liquids; and
those with strong intermolecular forces
are solids.
 Intermolecular forces include ion-dipole
forces, dipole-dipole forces, London
dispersion forces and hydrogen bonds.
 Physicals properties of liquids and solids
are explained by the kinetic molecular
theory.

 Liquids possess properties such as
viscosity, surface tension, capillarity
evaporation, boiling point, and critical
temperature and pressure.
 Heating curve is a plot of temperature
versus heat for phase changes.
 The properties of solids are explained
based on their nature and strength if
intermolecular forces of attraction.
 A phase diagram indicates the states or
phases of a substance under specific
temperatures and pressures.

Chapter 13. Solutions
Key Concept
 Solutions are homogeneous mixtures of two or
more substances in a single phase.
 A solutions is made of solute, the substance that
dissolves, and solvent, the substance in which the
solute is dissolved. A substance that dissolves in
another substance is soluble (miscible) and if it
does not, it is insoluble (immiscible).
 Solutions are either gaseous, liquids, or solid
solutions.
 In preparing dilute solutions form concentrated
solutions, the number of moles before dilutions is
equal to the number of moles after dilutions.

 Saturated solutions contains the
maximum amount of solute it can
dissolve at a given temperature.
 Unsaturated a solutions that contains
less than the maximum.
 Supersaturated a solution with more
than the maximum.
 Solubility is the extent to which a
solute dissolves in a given solvent.

Chapter 14. Chemical Kinetics
Key Concept
 Chemical kinetics is the study of rate
and sequence of steps by which chemical
reactions occur.
 The rate of a reaction is the measure of
how reactants turn into products.
 Collisions theory assumes that particles
collide at the proper orientation and with
sufficient energy in order to react.
 Activation energy is the minimum energy
required for a chemical reaction to occur
and make the reactant form an activated
complex or transition state.

 The factors that affect the rate at which a
chemical reaction proceed are nature of the
reactants, concentration of the
reactants, temperature at which reaction
occurs.
 A rate law for a reaction describes the
relationship between the concentration of
reactants and the reaction rate.
 Most chemical reactions proceed through a
series of elementary steps. The series of
steps called the reaction mechanism.
 The slow reaction in a reaction mechanism
called the rate-determining step.

Chapter 15. Thermo chemistry
Key Concept
 Thermodynamics is the study of processes which
involve heat transfer and the performance of
work.
 Thermochemistry is the study of this heat
exchange and work on chemical reactions.
 Energy + Energy = constant: law of conversation
of energy.
 3 types of system :
 Open
 Closed
 Isolated
 An open system allows the transfer of both
energy and matter into and out the system
through a boundary or wall.

 A closed system is only capable of
transferring energy through
boundary.
 An isolated system is not capable of
transferring both energy and matter
into and out of the system through a
boundary or wall.
 Heat is a transfer of energy between
system and surrounding due to
temperature difference.

Chapter 16. Chemical Equilibrium
Key Concept
 Equilibrium is a state at which there is
“balance of forces”.
 3 types of equilibrium:
 Mechanical
 Thermal
 Chemical
 Chemical equilibrium is achieved when
the rate of the forward reaction is equal
to the rate of the reverse reaction and
the amount of components remains
unchanged.

 Reversible reactions is an incomplete
reactions. The reaction is represented
by using a double headed arrow (═).
 Law of mass reaction states that the
compositions of a reaction mixture
can vary according to the quantities
of components that are present.

Chapter 17. Acids and Bases
Key Concept
 The operational definitions of acids
and bases are based on experimental
results from the laboratory which
includes color change using dyes.
 Arrhenius acids is a neutral substance
that ionizes when it dissolves in water
to give the H+ or hydrogen.
 Arrhenius base is a neutral substance
that gives the OH-, or hydroxide ion
when dissolves in water.

 Lewis defines an acids as species that
can accept a pair of electrons while a
base is a species that can donate a
pair of electrons.
 The degree of ionization, not the
concentration, classifies an acid or a
base as weak or strong.
 Compounds with more than one proton
to give are called polyprotic acids.

Chapter 18. Electrochemistry
Key Concept
 Electrochemistry is the branch of
chemistry that deals with electricity and
its relation to chemical reactions.
 A chemical reactions were loss of
electron(s)
is involved id called oxidation while
reaction where electron(s) is gained is
called reduction.
 Redox reaction can be balanced by using
the oxidation number method or the ion
electron method.

 Electrochemical cell, voltaic cell, or galvanic cell
converts chemical energy from spontaneous
reaction to produce electricity.
 Electrochemical cell is composed of the
electrodes and charge carriers.
 Anode is the electrode where oxidation occurs.
 Cathode is where reduction occurs or where
electrons are accepted.
 There 3 types of electrodes:
 Inert
 Metallic
 Membrane

Chapter 19. Nuclear Chemistry
Key Concept
 Many elements have at least one radioactivity
isotope or radioisotope. Elements with atomic
numbers 83 or greater are all radioactivity.
 Radioactivity decay of naturally occurring
radioisotope produces alpha particles, beta
particles, and gamma radiations.
 The half-life of a radioisotope is the time it takes
for one-half of a sample of the isotope decay.
 In artificial radioactivity or artificial
transmutation, the nucleus of an atom is
bombarded with a particle or radiation and
changed into different nuclei.

 In balancing nuclear equation, the sum
of the mass numbers and atomic
numbers of reactants must be equal
to the sum of the mass numbers and
atomic numbers of the product.
 The mass defect in a nucleus is due to
the strong forces of attraction that
bind nucleons together.

Chapter 20. Organic Chemistry
Key Concept
 Organic compounds are basically made up
of carbon atoms bonded mostly to
hydrogen, oxygen, nitrogen, and sulfur.
 Organic chemistry the study of the
carbon-based compounds.
 Hydrocarbons are made up of carbons
and hydrogens.
 Alkanes also called saturated
hydrocarbons, have an sp3
hybridization, four sigma bonds with no
pi bonds that can be bound to H or C
atoms.

 Alkenes are hydrocarbon containing a
carbon-carbon double bond.
 Alkynes are hydrocarbons containing a
carbon-carbon triple bond.
 Cycloalkanes are aliphatic cyclic (alicyclic)
compounds which have general ring
structure containing –CH-.
 A molecule can only be aromatic if it has the
following properties:
 (1) the molecule is planar and
 (2) has a monocyclic system of conjugation with a
total of (4n + 2) p electrons where n is an integer.

Chemistry finisher

More Related Content

What's hot

Similar to Chemistry finisher

More from mehhhh

Recently uploaded

Chemistry finisher