Vocab
What is a period on the periodic table?
A horizontal row in the periodic table, with seven total rows numbered 1 through 7.
Who first grouped elements into metals, nonmetals, gases, and earths in 1789?
Antoine Lavoisier.
The modern periodic table is based on what number?
The atomic number, or number of protons.
Which class of elements are the best conductors of heat and electricity?
Metals.
What is the name for the metals found in Groups 3 through 12?
Transition metals.
What is a group on the periodic table?
Each column in the periodic table.
What card game did Dmitri Mendeleev use as an approach for organizing the elements?
Solitaire
Across a period, do the number of valence electrons increase or decrease from left to right?
They increase.
What is the only metal that is a liquid at room temperature?
Mercury.
How many valence electrons do most elements need to be stable?
Eight
What is the Periodic Law?
The pattern of repeating properties across the periodic table.
What three things did Mendeleev list on his "deck of cards" for each element?
The element's name, mass, and properties.
Why do elements in a group have similar chemical properties?
Because they have similar electron configurations (the same number of valence electrons).
What class of elements has properties that fall between metals and nonmetals?
Metalloids
Group number matches the number of valence electrons for which groups?
The "A" groups (1 through 8)
What is an orbital?
A region of space around the nucleus where an electron is likely to be found.
Why did Mendeleev leave several gaps in his periodic table?
Because many elements had not yet been discovered.
What is the maximum number of electrons that can be held in energy level 4?
32.
If a nonmetal solid is hit with a hammer, it will crumble because it is what?
Brittle
Which element is a nonmetal but is located in a group with reactive metals?
Hydrogen
What are valence electrons?
Electrons that exist in the outermost energy level of an atom
What is the name of the element discovered in 1875 that filled the "eka-aluminum" gap?
Gallium (Ga).
How many total orbitals are found in energy level 3?
9.
Metals that can be drawn into thin wires are described as being what?
Ductile
Transition metals are known for their ability to form compounds with what visual feature?
Distinctive colors.