8th Grade Atoms and the Periodic Table Study Guide
What is a group or family of the periodic table?
A column (vertical)
What is a period of the periodic table?
A row (horizontal)
About how many elements are in the periodic table?
About 100
Where are semimetals/metalloids on the periodic table?
Bordering the zigzag line
In what order are the elements arranged? (By atomic number or atomic mass)
By atomic number
Which particle(s) create the volume of the atom?
Electrons
Why do elements in a family have similar properties?
Elements in a column have similar properties because they have the same number of valence electrons, the electrons in the highest energy level.
Nonmetals have a low melting temperature so most of them are which state of matter at room temperature?
Gas
How does the number of valence electrons change as you move from left to right across the table?
Group 1 has one valence electron. The number of valence electrons increases in columns to the right. Group 17 has 7 valence electrons and group 18 has 8 valence electrons.
Where are inert/noble gases on the periodic table?
Group 18, the far right column
When an atom gains or loses electrons an is no longer neutral, what is it called?
Ion
When atom have the same number of protons but a different number of neutrons, what are they called?
Isotopes
Where are metals on the Periodic Table?
Left of the zigzag line
What are the properties of the metalloids/semimetals?
Metalloids have some properties of metals and nonmetals and are semiconductors; they conduct electricity under certain conditions.
Are most of the elements metals, metalloids, or nonmetals?
Metals
Why are the elements in column 18 unreactive?
Noble gases are unreactive because their highest energy level is full (of valence electrons)
What are the three subatomic particles of an atom?
Proton, neutron, and electron
Which subatomic particle determines which element the atom belongs to?
Protons
What charge do the different subatomic particles have?
Protons - positive Neutrons - no charge Electrons - negative
Which two subatomic particles are equal in number in a neutral atom?
Protons and electrons
Which subatomic particles are in the nucleus?
Protons and neutrons
Which(s) contribute to the mass of the atom (atomic mass)?
Protons and neutrons in the nucleus
Where are nonmetals on the periodic table?
Right of the zigzag line
What are some properties of metals?
Shiny, hard, dense, good conductor of heat and electricity, high melting point and high boiling point.
Metals have a high melting temperature so most of them are which state of matter at room temperature?
Solid
Which elements are the most reactive metals?
The alkali metals (Group 1)
What are valence electrons?
The electrons in the highest energy level. These are the electrons involved in creating chemical bonds. The valence electrons are gained, shared, or lost to create chemical bonds.
Why are the alkali metals so reactive?
The elements in group 1 all have one electron in the highest energy level, so they lose or share the one electron easily.
Why are the halogens so reactive?
The elements in group 17 have seven electrons in the highest energy level, so the gain or share one electron easily.
Which elements are the most reactive nonmetals?
The halogens (Group 17)
What are the two main regions of an atom?
The nucleus and electron cloud.
What is the atomic number?
The number of protons
What are some properties on nonmetals?
The properties of nonmetals are opposite to those of metals.
What is an atom?
The smallest unit of an element that maintains the properties of that element.
What is the main property of the noble gases?
Unreactive or poorly reactive
