Download C1a 1.1 Atoms, Elements and Compounds

EDEXCEL C2
Lesson 1 - Elements and The
Periodic Table
Mrs Barnes
CCYD 2012-2013
Learning Objectives
By the end of this lesson you should be able to:
• Explain how Mendeleev arranged the elements into
what we know as the periodic table.
• Understand the importance of his ‘leaving gaps’ and
making predictions.
• State a definition for elements.
• Recognise names and symbols of elements.
• Find symbols for elements in the periodic table.
Success Criteria
• All of you will add the cause and symptoms of 3
diseases to your coursework sheets.
• Most of you will use the key words to recount the
virus infection.
• Some of you will complete the merit task of
annotating a cartoon strip.
Starter
• List …….
21 gaseous
elements
liquid element
atroom
room
at
4 metal
elements
3
5
non-metals
Solid
Elements
temperature
temperature
• Look at the things around you and
the substances that they are made
from- wood metal plastic and glass…
the list is almost endless.
• All substances are made of atoms.
We think there are about 100
different types of atom, there are
only about 100 different elements.
• Elements can have very different
properties. For example, elements
such as silver, copper and gold are
shiny solids. Other elements such as
oxygen, nitrogen and chlorine are
gases.
• History of the periodic table
• Dobereiner suggested that
elements could be grouped in
threes, (triads). Each member of
the triad had similar properties.
• History of the periodic table
• Newlands arranged elements in
order of increasing atomic mass.
He noticed that there was some
th
similarity between every 8
element. These were Newland’s
Octaves. The pattern broke
down because he did not leave
gaps for undiscovered elements.
• History of the periodic table
• Meyer looked at the relationship
between atomic mass and the density of
an element. He plotted a graph of
atomic volume against relative atomic
mass and obtained a curve with peaks
and troughs. Elements with similar
properties were in similar places on the
graph.
• History of the periodic table
• Mendeleev arranged elements in order
of atomic mass and took account of
similar properties. He left gaps for
undiscovered elements and even
predicted the properties these missing
elements should have.
Homework
• Find the periodic table in your
diary.
• You must learn the names,
symbols and order of the
first 20 elements.
• The symbols in the periodic table
represent atoms. For example, O
represents an
atom
of oxygen while
We
need
Na representstoanknow
atom of sodium.
The elements in the table are
all
about
arranged in vertical columns, called
later!!!
groups. Eachthis
group
contains
elements with similar chemical
properties.
Compounds
• Almost all of the substances around us
are not pure elements. Most substances
are made up of different atoms joined
together to form compounds. Some
compounds are made from just two
types of atom joined together (e.g.
water, made from hydrogen and
oxygen). Other compounds consist of
many different types of atom.
Key Points
• 1. All substances are made up of atoms.
• 2. Elements contain only one type of
atom.
• 3. Different atoms can bond together
by giving, taking or sharing electrons, to
form compounds.
Recap Learning Objectives
Can we all now:
• State a definition for elements.
• Recognise names and symbols of elements or
compounds.
• Find symbols for elements in the periodic
table.