Chapter 19: Elements and their Properties
Date:_____________
Section 1: The Periodic Table - Notes
Learning Goals:
 Explain the composition of the periodic table.
 Use the periodic table to obtain information.
 Explain what the terms metal, nonmetal, and metalloid mean.
Organizing the Elements:
 In the late 1800s, ___________________________________________ searched for a way to organize
the elements.
o
He arranged all of the elements known at that time in order of __________________________
______________________________________ and discovered a pattern.

All of the elements of the same ___________________ show similar properties.

When we arrange them in ___________, similar properties align in the same ____________________.

Because this pattern repeated, it was considered to be
______________________.

Periodic Table: a table that arranges the elements by increasing
______________________________ and by changes in physical and
chemical properties.

Mendeleev’s table was _______________________________.
o
Some elements on the current periodic table show
_____________________________ atomic mass from left to right.

_____________________________________ arranged the elements based on atomic number instead.
o
We still use this method today!
The Periodic Table:

All of the elements in the ____________ squares are metals.
o
Ex: __________________________________________________
o
Most metals are __________________ at room temperature
o
________________, can be drawn into wires, pounded into sheets, and are good conductors

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All of the elements in the green squares are ________________________.
o
Ex: ___________________________________________________
o
Most nonmetals are ___________________
o
Most are __________________, and are _______________ conductors of heat and electricity
All of the elements in the purple squares are ___________________________________.
o
Ex: _____________________________________________________
o
Have some properties of both _______________ and ____________________________
o
Also called _________________________
Vertical columns of elements are called ___________________ or families.
o

Elements in the ____________________________ have similar chemical properties.
Horizontal rows of elements are called _________________________.
o
Atomic number _____________________________ across a period.
Electron Cloud Structure:
 ____________________________ are responsible for giving groups of elements similar properties.

In a neutral atom, the number of electrons is __________________ to the number of protons.
o

Electrons within the electron cloud have different amounts of ______________________.
o

A carbon atom has _____ protons and _____electrons.
We model this difference by placing electrons into different ___________________________.
Energy levels ________________________ to the nucleus have ________________ energy than those
in the outer energy level.
Energy Levels:
 Energy levels are named using the numbers _____________.
o

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Each number corresponds to a __________ on the periodic table.
____________________________ and ______________________ are in the first row.
o
Their electrons only occupy energy level _______
o
Hydrogen has _______ electron in this level
o
Helium has _______ electrons in this level
Each energy level has a ______________________________ number of electrons that it can hold
o
Energy level 1 can hold _______ electrons
o
Energy level 2 can hold _______ electrons
o
Energy level 3 can hold _______ electrons
o
Energy level 4 can hold _______ electrons
Once one energy level is ________________________,
electrons start filling the next level.

It is the number of electrons in the _________________________________________ that determines
the chemical properties of the element.
o

________________________________: the electrons that occupy the outermost energy level.
Even though each energy level can hold a different total number of electrons, the outermost energy
level of an atom can only hold up to ________________________ valence electrons.

All elements in the same ________________ have the ______________ number of valence electrons.

Hydrogen, lithium, and sodium all have ___________ electron in their outermost energy level.
o
We can show this relationship by using ____________________________________________.
o
Electron dot diagram: uses the symbol of the element and ____________ to
represent _________________________ in the outermost energy level.


Practice: draw the electron dot diagram for the following elements:
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Lithium (Li)
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Bromine (Br)
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Strontium (Sr)
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Phosphorus (P)
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Argon (Ar)
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Oxygen (O)
The elements in Group 17 have electron dot diagrams similar to chlorine:
o
Because all members of a group have the _________________________________ of valence
electrons, they all undergo __________________________________________ in similar ways.

A common property of the elements in Group 17 is that they easily form compounds with elements
from Group 1.
o

Sodium and chlorine come together to form _______________________________________.
Not all elements will _______________________________________________ with other elements.
o
Elements in Group 18 have ___________ outer energy levels.

This causes these elements to be relatively ____________________________.