Reactivity of Elements

Reactivity in Elements

Reactivity: how easily or quickly a chemical reaction occurs.

Valence Electrons: Electrons in the outermost shell of an atom.

The number of valence electrons determines how and if the
element/atom will chemically react/bond.

If the outer shell is full, the element will
not react with other elements.

If the outer shell is NOT full, the element

will react with other elements.

Will this element
react?

Multiple Choice

Describes how likely an element is to form bonds with other elements.

• Reactivity

• Families

• Period

• Group

Multiple Choice

The number of valence electrons determines how and if the element/atom will chemically react/bond

• True

• False

Multiple Choice

How many valence electrons makes most atoms stable (nonreactive)?

• 2

• 8

• 1

• 4

Non-Reactive

Inert: means non-reactive

Multiple Choice

Elements that when put together are unable to react chemically.

• Metal

• Nonmetal

• Metalloid

• Inert

Valence Electrons and Groups

The Number of electrons is associated with the
element’s reactivity.

Elements with the same number of valence
electrons behave in similar way in reactions and
so are grouped together.

Elements in the same group share similar
properties.

Groups 1,2, and 17
are the most
Reactive Groups

Group 18 is Inert
(Non-Reactive)

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Multiple Choice

On the periodic table, reactivity increases as you move ______________.

• from right to left

• from left to right

Multiple Choice

Elements in the same group or family have _____________.

• the same number of valence electrons and different properties.

• the same number of valence electrons and similar properties

• different number of valence electrons and similar properties.

• different number of valence electrons and different properties.

Families of the Periodic Table

groups of elements with similar properties.

Multiple Choice

Elements in the same family or group have similar _______________.

• Protons

• Physical and Chemical Properties

• Shape

• Size

Alkali Metals-Group 1

Hydrogen is NOT a member, it is a
non-metal

Most Reactive because they are trying to get rid of their 1 valence electron

1 Valence Electron

Soft Metals, soft enough to cut with
butter knife

Very reactive, can explode when they are
exposed to water

Conduct Electricity

Multiple Choice

Which family of elements are the most reactive?

• Alkali Metals

• Alkaline Metals

• Halogens

• Nobel Gases

Alkaline Earth Metals

Location: Group 2

2 Valence Electrons

Reactive, but less than Alkali metals

Conduct electricity

Multiple Choice

Name this group: These metals are the second most reactive.

Transition Metals

Location: Groups 3-12

Good Conductors of heat
and electricity

Some are used for jewelry

Able to put up to 32
electrons in their second to
last shell

Halogens

Location: Group 17 - Has 7 Valence
Electrons

All are Non-Metals

Very Reactive, are often bonded with
elements from Group 1

Uses as disinfectants and to
strengthen teeth

*Most Reactive Non-Metal
Because they need 1 more valence electron to be stable

Multiple Choice

Which of the following is the most reactive group of non-metals? 

• Alkali

• Alkali Earth

• Halogen

• Noble Gas

Noble Gases

Location : Group 18- Has 8
Valence Electrons

Exist as gases

Non-MEtals

Not Reactive with other
elements because outer shell is
full

Used in lighted “neon” signs

Multiple Select

Group 18 also known as __________ or __________.

• noble gases

• alkali metals

• inert gases

​Important to Remember:

Elements in the same groups share the same properties

Group 1, 2 and 17 are the most Reactive Groups.
Group 17 is the most reactive Non-Metal
Group 18 is the most Inert (Non-Reactive) group.