Transcript Periodic Table

REVIEW: Parts of the Atom
Electron
Orbit
Neutron
Proton
Nucleus
Element, Compound, or
Mixture?
ELEMENT
COMPOUND
ELEMENT
MIXTURE
COMPOUND
MIXTURE
Review of the Periodic
Table
What is the symbol for Titanium?
Ti
_________
What is the atomic number of titanium?
titanium
22
Ti
47.867
22
_________
How many protons does titanium have?
22
_________
How many electrons does a neutral titanium
atom have?
22
__________
What is the atomic weight for titanium?
47.867
_______________
The Periodic
Table
The Periodic table as we know it
today was arranged by a Russian
Chemist named Mendeleev. He
arranged it according to the
physical and chemical
properties of the elements
Author: J R Reid
WORKSHEET 1
Complete the handout by writing the missing
chemical symbols in each box.
ON your periodic table
following:
Alkali
Alkaline Metals
Transition Metals
Poor metals
Halogens
Noble gases
Non metals
(given last lesson)
Label the
halogens
Arranging Elements
It is arranged in rows (across) called Periods
and columns (down) called Groups
Groups of elements show certain trends –
they have similar properties
Groups
Periods
Trends On The
Periodic Table
Author: J R Reid
Atomic Size
Atoms have certain sizes depending on:
The amount of electrons (negatives)
The pull from the nucleus (positive protons)
For the third period (row) the atomic radius for each
atom gets smaller across the table
Na
Mg
Al
Si
P
S
Cl
Ar
Even though the atoms have got more electrons
their electronegativity (pull for electrons) is
increasing because of increasing number of protons
Electronegativity
Electronegativity is the ability of a nucleus to attract
its valence/bonding electrons. It follows certain
trends on the table:
As you go across (left to right) it gets stronger
As you go up it gets stronger
e-
11
12
Na
e- eee-
13
e-
e-
Mg
Al
e-
e-
e-
e-
14
e-
e-
15
e-
Si
P
e-
e-
16
ee-
17
e-
S
Cl
What do you notice about the atomic number as you go across the period?
e-
19
e-
What about the number of orbitals as you go across the period?
What about the number of orbitals as you go down a group?
e-
K
Ar
e-
Increasing size
Size
Trends From Left to Right
Proton number and Atomic Mass increases
Atomic size decreases (more protons pulling the electrons)
Oxidising ability increases
Form ionic compounds to forming covalent
compounds
Melting Points from relatively high to relatively low
Form positive ions to form negative ions
Trends down a group
Proton number and Atomic Mass increases
Atomic size increases (adding more orbitals)
Metals become more reactive
Non-metals become less reactive
Valence Electrons
Valence electrons (also known as
valence) are the number of electrons
present in the outer most orbital.
What is the valence
of this sodium atom?
What is the valence
of this chorine atom?
Valence Electrons
The number of valence electrons of an
element is determined by its periodic
table group in which the element is
categorized.