The document provides an overview of key concepts in chemistry across multiple topics. It begins with definitions of chemistry and its applications. It then covers concepts related to matter, atomic theory, the periodic table, chemical bonds, reactions, stoichiometry, gases, solutions, kinetics, and more. For each topic, it lists several important terms and definitions.

1. The nature of Chemistry
Key Concepts

2. -is the study of matter and the changes
it undergoes. It is sometimes called the
central science because it overlaps with
many others science.

3. -is the application of science. It has
improved the quality of human life.

4. -are used to express physical quantities
in all science. Metric prefixed are used
to make units smaller or larger.

5. -is how close several measurement are to
the same value.

6. -tells how close a measurement is to true
or accepted value.

7. -include both the certain digits and the
estimated digit.

8. -is used to write very small or very large
numbers.

9. -is the technique that uses conversion
factors. The guide to ensure that
conversion factors are properly
formulated is the cancellation of units.

10. Matter: Its Composition and Organization
Key Concepts

11. -is anything that has mass and volume.
Properties of matter differ for solids,
liquids, and gases.

12. -is a substance that cannot be broken
down to simpler substance . A compound
is formed when two or more elements
combine in a chemical change.

13. -A change in the properties of a
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.

14. -A mixture has a variable composition. It
may be heterogeneous or homogeneous.

15. -Are mixtures of two or more solids,
liquids, or gases whose particle are
bigger than the particle of a solution
but smaller than those of a suspension.

16. -is the process of combining molecules to
form colloidal particles.

17. -is the process of breaking down large
particles to colloidal size.

18. -is the capacity to do work or to transfer
heat. Is is involved whenever matter
undergoes a change.

19. Atomic Theory
Key Concepts

20.  Over 2400 years ago, the concept of
the atom was proposed by Greek
philosophers.

21.  Thomson’s experiment on the behavior
of cathode rays in magnetic and electric
fields led to the discovery of the
electron and the measurement of its
charge to mass ratio.

22.  In the early 19th century, Dalton
proposed the atomic theory.

23.  Millikan’s oil drop experiment measured
the charge of the electron.

24.  Atoms have a nucleus that contains
protons and neutrons.

25.  Rutherford’s studies on alpha rays led
to the discovery of the nucleus.

26.  Becquerel and the Curies discovered
radioactivity.

27. Electronic Configuration
Key Concepts

28.  The properties of visible light and
other forms of electromagnetic
radiation led to the electronic
structure of atoms.

29.  Albert Einstein used Plank’s theory to
explain the photoelectric effect.

30.  Max Planck proposed that energy is
absorbed and emitted in discrete
amounts or individual packets called
QUANTA.

31.  The concept of quantized electrons
grew from the study of line spectra of
atoms.

32.  Louise de Broglie discovered the wave
nature of matter which initiated the
development of a new mathematical
description of electron configuration.

33.  Niels Bohr used the line spectra to
explain specific energy levels within the
atoms.

34.  Heisenberg’s uncertainly 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.

35. The Periodic Table
Key Concepts

36.  Different periodic tables were
developed by Dobereiner, Newlands,
Mendeleev, and Meyer.

37.  Atomic radius decreases down a group
because the electrons of the atoms fill
more energy levels.

38. -is the energy absorbed to remove an
electron to form a positive ion.

39. -is the energy change when an atom gains
an electron forming a negative ion.

40. Chemical Bounds
Key Concepts

41.  Chemical bonds are classified into three
group: ionic bonds, which are the
electrostatic forces between ions of
opposite charges; covalent bonds, which
result from the sharing of electrons by
two atoms.

42.  A polar covalent bond is formed when
electrons are not shared equally
between two atoms.

43.  Electro negativity deference of bonded
atoms determines the kind of bond
formed between the atoms.

44.  These bonds involved the valence
electrons with the tendency of atoms
to follow the octet rule.

45. Molecular Geometry
Key Concepts

46.  The shapes of small molecules can be
explained in terms of the VSEPR
model.

47.  The geometry of molecules is
determined by the arrangement of
bonding pairs and lone pairs.

48.  The five common shapes of small
molecules are linear, trigonal planar,
tetrahedral, trigonal bipyramid, and
octahedral.

49. Chemical Names and Formulas
Key Concepts

50.  The charges or oxidation numbers of the ions
of representative elements are determined
by their position in the periodic table.

51.  Most transition metals have more than one
common ionic or oxidation numbers. A
polyatomic ion a group of atoms that
behaves as an ion that has a change.

52.  Binary ionic compounds are named by writing
the name of the caution followed by the
name of the anion. Binary compounds end in
–ide. If caution have more than one ionic
charge, a roman numeral is used in the name.

53.  Ternary ionic compounds contain at least one
polyatomic ion. The names of these
compounds end in -ite or-ate.

54.  Bases are compounds containing a metal ion
and hydroxide ion(OH-). Bases are named by
writing the name of the caution followed by
hydroxide.

55. Chemical Reaction
Key Concepts

56.  Chemical reaction are represented by
chemical equations.

57.  The substances that undergo chemical
changes are the reactant and the substances
formed are the products.

58.  In a combination reaction, two or more
element or compound combine to produce a
single product.

59.  In a decomposition reaction, a single
chemically active element displace a
substance below it in the activity series.

60.  A double replacement reaction involves the
exchange of caution and anions between two
compounds. Replacement reaction can be
written as net ionic equations.

61.  In a combustion reaction, oxygen is always
one of the reactants.

62. Stoichiometry
Key Concepts

63.  A mole is the amount of substance that
contains 6.02 * 10 to the power of 23 particle
or species.

64.  The representative particles of elements are
the atoms.

65.  Molecules are representative particles of
molecular compounds and diatomic
elements.

66.  Percent composition of a compound is the
percent by mass of each element in a
compound.

67.  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.

68.  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.

69.  The theoretical yield is the amount of product
obtained when all of the limiting reagent is
used up.

70.  The actual yield is the product formed when
the actual reaction is carried out.

71. Gases
Key concept

72.  The physical properties of gases are given by
four quantities:
 Pressure P
 Volume V
 Temperature T
 Amount of Gases n

73.  The behavior of gases can be explained by
the kinetic molecular theory.

74.  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).

75.  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.

76.  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.

77. Liquids and Solids

78.  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.

79.  Intermolecular forces include ion-dipole
forces, dipole-dipole forces, London
dispersion forces and hydrogen bonds.

80.  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.

81.  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.

82.  A phase diagram indicates the states
or phases of a substance under
specific temperatures and pressures.

83. Solutions

84.  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.

85.  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.

86.  In preparing dilute solutions form
concentrated solutions, the number of
moles before dilutions is equal to the
number of moles after dilutions.

87.  Saturated solutions contains the
maximum amount of solute it can
dissolve at a given temperature.
 Unsaturated a solutions that contains
less than the maximum.

88.  Supersaturated a solution with more
than the maximum.
 Solubility is the extent to which a solute
dissolves in a given solvent.

89. Chemical Kinetics

90.  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.

91.  Collisions theory assumes that particles
collide at the proper orientation and
with sufficient energy in order to react.

92.  Activation energy is the minimum
energy required for a chemical
reaction to occur and make the
reactant form an activated complex
or transition state.

93.  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.

94.  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.

95.  The slow reaction in a reaction
mechanism called the rate-
determining step.

96. Thermochemistry

97.  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.

98.  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.

99.  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.

100. Chemical Equilibrium

101.  Equilibrium is a state at which there is
“balance of forces”.
 3 types of equilibrium:
 Mechanical
 Thermal
 Chemical

102.  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.

103.  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.

104. Acids and Bases

105.  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.

106.  Arrhenius base is a neutral substance
that gives the OH-, or hydroxide ion
when dissolves in water.

107.  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.

108.  Compounds with more than one
proton to give are called polyprotic
acids.

109. Electrochemistry

110.  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.

111.  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.

112.  Electrochemical cell is composed of
the electrodes and charge carriers.

113.  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

114. Nuclear Chemistry

115.  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.

116.  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.

117.  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.

118. Organic Chemistry

119.  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 hydrogen.

120.  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.

121.  Alkynes are hydrocarbons containing
a carbon-carbon triple bond.

122.  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.