MELCS
TOPIC 1
1.1 the formation of the elements during the Big
Bang and during stellar evolution
1.2. the distribution of the chemical elements and
the isotopes in the universe
1.3 Explain how the concept of atomic number
led to the synthesis of new elements in the
laboratory
MELCS
TOPIC 2
1. how the uses of
different materials are
related to their
properties and structures
2. the relationship
between the function
and structure of
biological
macromolecules
2.1 Determine if a molecule is polar or nonpolar
given its structure
2.2 Relate the polarity of a molecule to its
Properties
2.3 Describe the general types of intermolecular
Forces
2.4 Explain the effect of intermolecular forces on
the properties of substances
2.5 Explain how the structures of biological
macromolecules such as carbohydrates, lipids,
nucleic acid, and proteins determine their
properties and functions
TOPIC 3
1. the following aspects
of chemical changes:
a. how fast a reaction takes
place
b. how much reactants are
needed and how much
products are formed in a
reaction
c. how much energy is involved
in a reaction
2. how energy is harnessed
MELCS
3.1 Use simple collision theory to explain the effects of
concentration, temperature, and particle size on the rate of
reaction
3.2 Define catalyst and describe how it affects reaction rate
3.4 Determine the limiting reactant in a reaction and calculate
the amount of product formed
3.5 Describe how energy is harnessed from different sources:
A. Fossil fuels
B. Biogas
C. Geothermal
D. Hydrothermal
E. Batteries
F. Solar cells
G. Biomass
TOPIC 4
The properties and
mode of action of the
following consumer
products:
a. cleaning materials
b. cosmetics
MELCS
4.1 From product labels, identify
the active ingredient(s) of cleaning
products used at home
4.2 Give the use of the other
ingredients in cleaning agents
HISTORY OF
THE
UNIVERSE
TRUE OR FALSE
Elements are made up of
Sub-atomic particles
called protons, neutron
and electrons.
TRUE OR FALSE
The identity of an
element depends on how
many neutrons it has.
TRUE OR FALSE
Lithium is one of the
elements formed during
the Big Bang
TRUE OR FALSE
Nucleosynthesis combines
nucleons (protons and
neutrons) to form
TRUE OR FALSE
The Big Bang is an
explosion.
TRUE OR FALSE
The Universe was
colder 13.8 billions
years ago.
TRUE OR FALSE
The higher the energy of the
particles in an object are,
the higher the temperature
of that object will be.
TRUE OR FALSE
Mass can be converted
into energy.
What happens in the beginning?
BIG BANG THEORY
The Big Bang Theory is an effort
to explain what happened of the
very beginning of our Universe.
Our Universe sprang into
existence as “singularity” around
13.7 billion years ago.
Big Bang Theory
Postulates that the
universe emerged from a
state of enormous density
and energy. Everything
came from a single point
and expanded to now what
we call the universe. It is
proposed by Georges
Lemaitre.
EVIDENCES OF BIG BANG



Cosmic expansion, Edwin
Hubble
Cosmic Microwave background,
George Gamow
Primordial or Big bang
Nucleosynthesis
EXPANSION
Every galaxy is rushing away from us with a
speed which is in direct proportion to its
distance, known as Hubble’s Law, so that
a galaxy that is twice as far away as another
is receding twice as fast, one ten times as far
away if receding ten times as fast, etc.
The existence of the cosmic microwave
background (CMB) was postulated on
theoretical grounds in the late 1940s by
George Gamow, Ralph Alpher, and Robert
Herman, who were studying the
consequences of the nucleosynthesis of light
elements, such as hydrogen, helium and
lithium, at very early times in the Universe.
How elements formed?
NUCLEOSYNTH
ESIS
- the formation of atomic nuclei
(center of atoms- protons and
neutrons)
- occurred right after the Big Bang
- started as quarks forming the
protons and neutrons
THREE TYPES OF
NUCLEOSYNTHESIS
●
●
●
Big Bang
Nucleosynthesis
Stellar Nucleosynthesis
Supernova
Star


Stars must have energy to exist for a
certain length of time.
Energy comes from various nuclear
fusion reactions between light elements,
involving the release of a huge amount of
energy that keeps the star hot
The word “stellar”
means star and the
formation of elements in
the center of the star is
called stellar
nucleosynthesis.
The star is unable to generate heat when it runs
out of hydrogen in its core leading to its
contraction and expansion.
● Red giant star becomes exhausted of nuclear
fuel, the outer material is blown off into space
leaving the inert Carbon. The remnant is known
as WHITE DWARF.
● This is said to be the remain of the white dwarf
that cooled down and no longer emits light and
heat. The hypothetical BLACK DWARF.
●
A more massive main sequence star evolves, cools
and expands faster than low mass star and will turn
into RED SUPER GIANT star, the largest known star.
Carbon fusion still occurs and Oxygen formed.
● Explosion of a star or SUPERNOVA releases large
amount of energy. Because of that, elements are
dispersed into the space.
● BLACK HOLE is a region in space where gravity is
too strong that no matter can escape from it.
● It is believed that a NEUTRON STAR is formed from
Supernova explosion. This is also the smallest star.
●
RED GIANT
Produced
elements such as
Beryllium,
Carbon up to
Oxygen
SUPER RED
GIANT
Produced
elements such as
Neon, Silicon up
to Iron.
34
35
Proton- Proton Chain
Reaction in main
sequence star. This is
the process by which
average star gets
their energy and
convert Hydrogen into
Helium.
36
CNO (Carbon,
Nitrogen, Oxygen)
CYCLE
Conversion of
Hydrogen to Helium
among massive stars
by using Carbon as
catalyst.
WHAT HAPPENS
ONCE A STAR HAS
USED UP THE
HYDROGEN IN ITS
CORE?
38
TRI- ALPHA PROCESS
39
ALPHA LADDER PROCESS
A star accumulates more mass and
continues to grow into red super
giant. Alpha particle fusion
happens at its core and creates
more heavy elements until
elements called Iron is formed.
HOW DO ELEMENTS
HEAVIER THAN
IRON FORM?
The explosion of star or supernova is believed
to be the source of other elements heavier
than Iron. During the explosion, these heavy
elements are dispersed into the space. Aside
from gases Hydrogen and Helium in space,
other evidence of star formation is the energy
emitted during nuclear reaction. It is also the
energy emitted by different forms of radiation
such as UV, Infrared, X-ray, radio wave and
microwave.
You will write a story which
relates the events of your life
from past, present and future
to the life cycle of a star. Use
also those elements which
could symbolize something or
anything in your story.
46
1. What element from space is
pulled by gravity and turn into a
protostar?
2. How are heavy elements such
as Carbon, Oxygen and Neon
formed during star formation?
THE ATOMIC
NUMBER AND
THE SYNTHESIS
OF NEW
ELEMENTS
ATOMS- the
smallest units or
particles of
matter that have
all the properties
of an element.
Leucippus and Democritus
Leucippus proposed that matter is made up of indivisible
particles or atomos (the modern word atom is derived from
this term).
● Leucippus started this idea and thought that atoms had to
exist because things were constantly changing in nature.
● Further concept of atom was actually preserved and
developed by Democritus. According to him, atoms are
indivisible and uncuttable, thus regarded as the basic building
blocks of nature and universe. For Democritus, matter is
composed of empty space through which atoms move.
●
●
Aristotle rejected the idea of Leucippus
and Democritus. He did not believed that
the nothingness of empty space could
not exist. He thought that all materials on
earth were not made of atoms but of four
elements, Earth, Fire, Water, and Air.
●
In 1803, John Dalton (regarded as the
Father of Atomic Theory) presented the
Atomic theory know as Dalton’s Atomic
Theory.
How can Elements
be made in
Laboratories?
HENRY GWYN-JEFFREYS
MOSELY- He was an
English physicist whose
experiment demonstrated
that the major properties of
an element are determined
by the atomic number, not
by the atomic weight, and
firmly established the
relationship between
atomic number and the
charge of the atomic
nucleus.
In 1913, Moseley used Rutherford’s work to
advance the understanding of the elements
and solve the problem with Mendeleev’s
periodic table.
● Moseley noticed that shooting electrons at
elements caused them to release x-rays at
unique frequencies. He also noticed that the
frequency increased by a certain amount
when the “positive charge” of the chosen
element was higher.
●
●
He used X-ray spectroscopy to determine the
atomic number of an element. He bombarded a
beam of electrons to different elements and
measured their X-ray spectral lines. His results
clearly showed that frequency of the X-rays
given off by an element was mathematically
related to the position of that element in the
Periodic table. The frequency is proportional to
the charge of the nucleus, or the atomic
number.
The electron configuration of an atomic
species (neutral or ionic) allows us to
understand the shape and energy of its
electrons.
● Knowing the electron configuration of a species
gives us a better understanding of its bonding
ability, magnetism and other chemical
properties.
●
●
The electron configuration is the
standard notation used to describe the
electronic structure of an atom. Under
the orbital approximation, we let each
electron occupy an orbital, which can be
solved by a single wavefunction.
●
Hence, many of the rules that we use to
describe the electron's address in the
hydrogen atom can also be used in
systems involving multiple electrons.
When assigning electrons to orbitals, we
must follow a set of three rules: the
Aufbau Principle, the Pauli-Exclusion
Principle, and Hund's Rule.
VALENCE ELECTRONS
●
a single electron or one of two
or more electrons in the outer
shell of an atom that is
responsible for the chemical
properties of the atom.
RULES IN WRITING LEWIS DOT
STRUCTURES
Step 1: Find the Total Number of Valence
Electrons
Step 2: Put the least electronegative atom
in the center.
Step 3: Hydrogen always goes outside.
RULES IN WRITING LEWIS DOT
STRUCTURES
Step 4: Complete octets on the atoms.
Step 5: If central atom does not have an
octet, move electrons from the outer
atoms to form double or triple bonds.
Chemical Bonding
●
refers to the interactions that lead to
the association
of atoms into molecules, ions, cryst
als, and other stable species that
make up the familiar substances in
our everyday world.