periodic table of elements by: suad, khadija & sahra
TRANSCRIPT
Reviewing the Atom...● The first official discovery of the atom was by Dalton who came up with a atomic theory which
stated:
o All elements are composed of tiny indivisible particles
o Atoms of the same element are identical. The atoms of any one element are different
from those of any other element
o Atoms of different elements can physically mix together or can chemically combine in
simple whole-number ratios to form compounds
o Chemical reactions occur when atoms are separated from each other, joined, or
rearranged in a different combination. Atoms of one element, however, are never
changed into atoms of another element as a result of a chemical reaction
● After Dalton a new explosion of studies around this area of chemistry erupted
o Schrodinger devised the quantum mechanical model
o Thomson discovered the electron, as well as isotopes.
o Rutherford discovered that there was a nucleus in atoms
o Bohr proposed that electrons had energy levels and that they revolved around the atomic
nucleus but electrons can jump from one energy level (or orbit) to another.
o Dobereiner organized elements into triads
o Mendeleev was known for creating the first version of the periodic table
Reviewing Atomic Make-up...The atom is divided up into three parts which vary from element to
element. The neutrons added to the protons is called the mass number.
Neutrons
● a subatomic particle
found in the nucleus like
proton but without an
electric charge
● They help determine an
atom's isotope
● Mass is that of 1 mass
unit
Protons
● a subatomic particle in
an atom's nucleus, with a
positive electric charge
● They also determine an
atom's atomic number
● Mass is that of 1 mass
unit
Electrons
● a subatomic particle with
a negative electric
charge
● They help determine an
atom's ability to bond
and location on the
periodic table
● Mass is 1/1840 relative
to the mass of proton
Organizing the Periodic TableThere are many ways to organize the periodic table;
1. You can divide it up into Metals, Non Metalsand Metalloids (shown below)
2. You can divide up the elements on the table
by Alkali Metals, Alkaline Earth Metal, Transitional
Metals, Inner Transitional Metals, Halogens, Metals, Non Metals,
Metalloids and Noble gases (shown right)
What Makes NOBLE GASES special
The noble gases are located in the far right of the periodic table and were
previously referred to as the "inert gases" due to the fact that their filled
valence shells, making them extremely unreactive. The elements in this group
are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon
(Rn).
The ACTINIDE Period...
They are all radioactive and some are not found in nature. Some of the
elements with higher atomic numbers have only been made in labs. This atoms that
are made in lab usually have short life-spans. The elements from 99-103 are
synthetic, and 89-98 are occur naturally from different circumstances. The elements
in this period include actinium (Ac), thorium (Th), protactinium (Pa), uranium (U),
neptunium (Np), plutonium (Pu) americium (Am), curium(Cm), berkelium (Bk),
californium (Ca), einsteinium (Es), fermium (Fm), mendelevium (Md), nobelium (No),
lawrencium (Lr).
The LANTHANIDE Period...
Unlike Actinides, all the Lanthanides occur naturally in nature. The
elements of this section of the period table are lanthanum (La), Cerium (Ce),
Praseodymium (Pr), Neodymium (Nd), Promethium (Pm), Samarium (Sm),
Europium (Eu), Gadolinium (Gd), Terbium (Tb), Dysprosium (Dy), Holmium (Ho),
Erbium (Er), Thulium (Tm), Ytterbium (Yb), and Lutetium (Lu)
What Make HALOGENS special
The halogens are located on the left of the noble gases on the periodic table.
These five toxic, non-metallic elements make up Group 17 of the periodic table and
consist of: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At).
Although astatine is radioactive it is often included in the halogen group. Because the
halogen elements have seven valence electrons, they only require one additional
electron to become “happy” atoms. This characteristic makes them more reactive
than other non-metal groups.
ALKALINE EARTH METAL Family
They are all shiny, silvery-white, somewhat reactive metals and are most
likely gonna lose their two outermost electrons to form cations with a positive
charge. The alkaline earth metals are beryllium (Be), magnesium (Mg), calcium (Ca),
strontium (Sr), barium (Ba), and radium (Ra). They are in the second group and
therefore have 2 valence electrons. All the discovered alkaline earth metals occur in
nature.
ALKALI METALS FamilyAlkali metals are among the most reactive metals. This is due in part to their
larger atomic radii and low ionization energies. They tend to donate their electrons in reactions a become positive cation. The alkali metals include: lithium (Li), sodium (Na), potassium (K), rubidium (RB), cesium (Cs), and francium (Fr), hydrogen (H)
Metals, Nonmetals & Metalloids
When you divide the Periodic Table into three general groups you come up with Metals, Nonmetals and Metalloids
Metals
● Makes up 80% of the
table. It includes areas
like the transition
metals and alkali metals
● Some notable qualities
are their sheen,
conductibility, that their
ductile and malleable,
metals are also solid at
room temp.
Nonmetals
● Is mostly found in the
upper-right corner
except for hydrogen
which is on the left.
Includes noble gases
● Some notable qualities
are that they the are
poor conductors and
most gases at room
temp.
Metalloids
● The metalloids part of
the periodic table is the
stepping stair between
the metals and
nonmetals
● Share qualities of both
metals and nonmetals
Important Terms to Know!● Octet Rule- That when forming compounds, elements like to have similar electron
configurations to noble gases, which is to have eight electrons in their highest occupied shell
● Valence Electrons- Are the electrons in the highest occupied shell of an atom
● Cations- An ion with a positive charge
● Anion- An ion with a negative charge
● Ion- Is an atom or group of atoms that has a positive or negative charge. This is dependant on if the electrons in an atom is equal to the protons in an atom
● Ionization Energy- The energy required an electron from an atom
● Electronegativity- Is the ability of an atom of an element to attract electrons when the atom is in a compound