Why is electron arrangement important?
It determines certain properties of an elements such as conductivity and reactivity
In what way are electrons arranged in?
They are in energy levels, which are regions around the nucleus
Why are valence electrons important?
They determine how an element will react with other elements
Why are elements grouped?
They have similar properties
How are rows on the periodic table arranged?
The elements increase by atomic number and atomic mass
What type of elements are on the left side?
Metals
What type of elements are on the right side?
Nonmetals
What type of elements are found in between?
Metalloids
What are the elements found in groups 3-12 and why?
They are transition metals because they do not follow the regular pattern
Why is hydrogen placed in group one even though it is unique?
It has only one valence electron
What is the similar characteristic of elements in the same period?
They have the same number of energy levels
What is the most abundant element in the universe?
Hydrogen
What is group 1 called?
Alkali Metals
What do Alkali Metals contain?
Metals
How many valence electrons do Alkali Metals have?
One
How reactive are Alkali Metals?
Very reactive
What are shared properties of Alkali Metals?
Soft; silver colored; shiny; low density
What is group 2 called?
Alkaline-Earth Metals
What does Alkaline-Earth Metals contain?
Metals
How many valence electrons do Alkaline-Earth Metals have?
Two
How reactive are Alkaline-Earth Metals?
Very reactive, but not as reactive as Alkali Metals
What are some properties of Alkaline-Earth Metals?
Silver colored; more dense than Alkali Metals
What are groups 3-12 called?
Transition Metals
What do Transition Metals contain?
Metals
How many valence electrons do Transition Metals have?
One or two
How reactive are Transition Metals?
Less reactive than Alkaline-Earth Metals
What are some properties of Transition Metals?
Shiny; good conductors of thermal energy and electric current; higher densities and melting points (except for mercury) than elements in groups 1 or 2
What is group 13 called?
Boron Group
How many valence electrons does Boron Group have?
Three
How reactive are elements in Boron Group?
Reactive
What is a shared property of elements in Boron Group?
Solid at room temperature
What is group 14 called?
Carbon Group
How many valence electrons does Carbon Group contain?
4
How reactive is Carbon Group?
Varies
What is a shared property of the Carbon Group?
Solid at room temperature
What is group 15 called?
Nitrogen Group
How many valence electrons does Nitrogen Group have?
5
How reactive are elements in Nitrogen Group?
Varies
What is a shared property of the Nitrogen Group?
All but nitrogen are solid at room temperature
What is group 16 called?
Oxygen Group
How many valence electrons does Oxygen Group have?
6
How reactive is Oxygen Group?
Reactive
What is a shared property of Oxygen Group?
All but oxygen are solid at room temperature
What is group 17 called?
Halogens
What do Halogens contain?
Nonmetals
How many valence electrons do Halogens have?
7
How reactive are Halogens?
Very Reactive
What are shared properties of Halogens?
Poor conductors of electricity and electric current; react violently with Alkali Metals to form salts; never found uncombined with nature
What is group 18 called?
Noble Gases
What do Noble Gases contain?
Nonmetals
How many valence electrons do Noble Gases have?
8 (two for helium)
How reactive are Noble Gases?
Not reactive
What are shared properties of Noble Gases?
Colorless, odorless, and gases at room temperature
What are the most reactive nonmetals?
Halogens
What are the electrons outermost energy level?
Valence electrons
How many electrons can the first energy level hold?
Two
How many electrons can the second energy level hold?
Up to eight
What do atoms of MOST nonmetals have?
Most of them have a complete set of valence electrons
What do atoms of MOST metalloids have?
Most have about half a complete set of valence electrons
What do groups 1 & 2 tend to do when they react?
Lose electrons
How many electrons do Halogens gain?
One
Which group has a complete set of valence electrons?
Noble Gases 18
What does mass equal?
Protons+Neutrons
What does the atomic number equal?
#Protons
What do electrons equal?
#Protons
How do you find the number of neutrons?
Mass-#Protons
