10/8/2015
Groups of the Periodic
Table
Nonmetals, Noble Gases…
1
10/8/2015
Metalloids
Elements that have properties of
metals and nonmetals
Metalloids
► These
elements are found along the stairstairstep line that separates the transition
metals from
the nonmetals
2
10/8/2015
Metalloids can be conductors (like metals) or
insulators (like nonmetals). The ability to become
either a conductor or an insulator has made
metalloids the basis of the computer chip industry
and “Silicone Valley.”
3
10/8/2015
Nonmetals
Hydrogen, Halogens, Noble Gases
4
10/8/2015
Hydrogen
5
10/8/2015
Hydrogen
► Atomic
number 1 on the periodic table
► Makes up 90% of all the atoms in the
universe.
► Diatomic molecules–
molecules– consists of two atoms
of the same element
Ex. Hydrogen is found in nature as H2
6
10/8/2015
Diatomic Molecule
► Def:
Elements that
are found in nature
as two atoms of the
same element
Examples
O2
N2
H2
Uses of Hydrogen
7
10/8/2015
8
10/8/2015
9
10/8/2015
10
10/8/2015
Dirigible
11
10/8/2015
The Hindenburg
Who would have guessed a ship filled with
explosive gas was a bad idea (35 dead)
12
10/8/2015
The most abundant element in the universe!
Halogens
13
10/8/2015
Halogens
► Found
in group 17 of the periodic table
► Can bond to only one other atom
► Often bond to Group 1 elements (Alkali
Metals)
This combination of a metal (alkali - group 1)
and a nonmetal is called a salt.
salt.
14
10/8/2015
Uses of Halogens
Fluorine
F
15
10/8/2015
16
10/8/2015
Chlorine
Cl
17
10/8/2015
18
10/8/2015
Bromine
Br
19
10/8/2015
Flame--Retardant Clothing
Flame
Iodine
I
20
10/8/2015
Noble Gases
A group of inert gases that almost
never form a compound
“inert”
21
10/8/2015
Noble Gases
► Group
18
► Full outer level of electrons, so there is no
room for bending with another atom to form
a compound
This makes them vary stable compounds, rarely
reacting with anything
22
10/8/2015
Uses of Noble Gases
Helium
He
23
10/8/2015
In 2008 a man flew 235
miles in a lawn chair with a
bunch of balloons tied to it,
relying on the fact that
helium is less dense than air.
24
10/8/2015
25
10/8/2015
26
10/8/2015
Neon
Ne
27
10/8/2015
Argon
Ar
Comes from the Greek word for
“lazy,” as its discoverers were
amazed at how they couldn’t get
it to do anything…
Used in containers to replace oxygen, which is highly
reactive with certain elements (which ones???)
28
10/8/2015
Incandescent bulbs
are filled with argon
to prevent the
filaments from
oxidizing
29
10/8/2015
Noble Gases & Mass
► Which
A)
B)
C)
D)
E)
weighs more?
1 L of helium
1 L of neon
1 L of argon
1 L of krypton
They all weigh the same
Watch the video and find out!
The End!
30