2. Vocabulary
Nouns
Occurrence
Abundance
Earth’s crust
Sodium
Living things
Grouping
Verbs
To house
To constitute
To carry out
To make up
To be made up (of)
To tend
Adjectives
Vital
Common
Variable
Abundant
3. Abundance of Elements in Nature
Of the 118 elements that appear in the PeriodTable,
the Earth houses 90.The elements that come after
Uranium (atomic number 92) are not found in
nature, and have been obtained artificially.
4. Hydrogen (H) and Helium (He)
Hydrogen and Helium are the most abundant elements in the
Universe.
Because H and He are small, they formed very quickly in the
first few seconds after the Big Bang.According to the Big
Bang theory, four minutes after the start of our Universe, its
chemical composition by mass was 76% H and 24% He.
5. Non-metals: Abundant in living
organisms and the atmosphere
Living things on Earth are mostly composed of elements from
groups 14 to 17 of the PeriodicTable, according to the following
proportions:
Primary Bioelements: Constitute 96% of living matter: C, H, O,
N, S and P. (Carbon, Hydrogen, Oxygen, Nitrogen, Sulfur, and
Phosphorous).
Secondary Bioelements:They are important for carrying out
vital functions, and make up 3.3%: Ca, Na, K, Mg, Cl
Oligoelements :Appear in living matter in amounts less than
0.1%: Some include: Fe, Mn, Zn, F, I B, Si,V, Co, Se, Mo, Sn.
6. Metals: the most numerous, in small
quantities
Of all of the elements of the PeriodicTable, approximately
four fifths (4/5) are metals!
However, they are also the least abundant in Nature.
In fact, even in the Earth’s Crust, O and Si make up about
73% and they are non-metals.Then there’s: Al (aluminum),
Fe (iron), Ca (calcium), Na (sodium), K (potassium) and
Mg (magnesium); and, in much smaller proportion, the rest.
7. Sodium-Potassium Pump
An example of a vital bodily function that requires
Potassium (K) is the sodium-potassium pump that
regulates the concentration of chemicals within the
cells of living organisms, including humans!
8. Semi-metals:
components of the electronic age
The elements situated on the border between metals and
non-metals have their own characteristics. Elements such as
Si (silicon), Ge (germanic), or As (arsenic) are called semi-
conductors and are the basic components of current
electronics.
9. Review:
How many elements are there?
How are they organized in the PeriodicTable?
a. By their radioactivity
b. By the number of protons they have
c. By the number of neutrons they have
d. By the number of isotopes they have
Which elements in the periodic table are non-metals?
Which elements in the periodic table are metals?
12. Vocabulary II
Nouns
Electronegativity
Gout (drop)
Octet rule
Cation
Anion
Lattice
Joint
Accordance
Wire
Hint
Adjectives
Electronegative
Ambient (as in ambient
temperature)
Phrases
In order to
Verbs
To share
To gain
To accept
To lose
To get rid of (to escape)
14. Molecules
Molecules are generally small substances, and formed by a
definite or certain number of atoms.They can be:
Elemental Molecules: formed from one element
Ex.: O3, which makes up the ozone layer
that protects us from UV radiation.
Compound Molecules: formed from different atoms.
Ex.: Carbon dioxide (CO2), or Sulfur trioxide (SO3).
15. Crystals
Crystal nets are generally big substances, and are formed
by a variable number of atoms, ions, or molecules that tend
to form a regular three dimensional structure.
Just like molecules, crystals can be:
Elemental crystals: formed by identical atoms.
Ex: Nickel (Ni), diamond (C)
Compound crystals: formed by different atoms.
Ex: Sodium chloride (NaCl) = Table Salt
Cl-
Na+
16. Molecules vs. Crystals
Usually very small
Made up of a definite
number of atoms.
Can be elemental or
compound.
Usually very big
Made up of a variable
number of atoms, ions
or molecules.
Can be elemental or
compound.
17. Are there crystals in our bodies?
Crystals can sometimes be formed in the human body.
For example, urea crystals
found in a urine sample
indicate high levels of uric acid in
the blood.This situation presents as
the disease gout (la gota), in which
crystals form in joints.
Uric acid crystals from a
fluid sample photographed
under a microscope.
18. Molecule or Crystal?
1.“A stable grouping of atoms is formed by thousands of
identical atoms organized in space.”
Will it be a molecule or crystal?
Elemental type or compound type?
2.“A stable grouping of atoms is formed by 3 atoms: 2 of
oxygen and 1 of sulfur.”
Are we talking about a molecule or crystal?
Elemental type or a compound type?
19. Molecule or Crystal?
1.“A stable grouping of atoms is formed by thousands of
identical atoms organized in space.”
Will it be a molecule or crystal?
Elemental type or compound type?
2.“A stable grouping of atoms is formed by 3 atoms: 2 of
oxygen and 1 of sulfur.”
Are we talking about a molecule or crystal?
Elemental type or a compound type?
20. Molecule or Crystal?
1.“A stable grouping of atoms is formed by thousands of
identical atoms organized in space.”
Will it be a molecule or crystal?
Elemental type or compound type?
2.“A stable grouping of atoms is formed by 3 atoms: 2 of
oxygen and 1 of sulfur.”
Are we talking about a molecule or crystal?
Elemental type or a compound type?
21. Molecule or Crystal?
1.“A stable grouping of atoms is formed by thousands of
identical atoms organized in space.”
Will it be a molecule or crystal?
Elemental type or compound type?
2.“A stable grouping of atoms is formed by 3 atoms: 2 of
oxygen and 1 of sulfur.”
Are we talking about a molecule or crystal?
Elemental type or a compound type?
22. Molecule or Crystal?
1.“A stable grouping of atoms is formed by thousands of
identical atoms organized in space.”
Will it be a molecule or crystal?
Elemental type or compound type?
2.“A stable grouping of atoms is formed by 3 atoms: 2 of
oxygen and 1 of sulfur.”
Are we talking about a molecule or crystal?
Elemental type or a compound type?
