The name for Dobereiner's group of three elements
What is a triad?
A horizontal row in the periodic table
What is a period?
Groups 1 and 2 make up the ___ - block
What is "s"?
An atom or group of atoms that has a positive or negative charge
What is an ion?
Type of element that is a good conductor of heat and electricity
What is a metal?
Elements in the modern periodic table are organized by this.
What is increasing atomic number?
Strontium is an example of this type of element
What is an Alkaline Earth metal?
Element that ends in 3p3
What is Phosphorus (P)?
One-half the distance between the nuclei of of two atomic that are joined
What is atomic radius?
This group of elements is stable and not reactive
What are the noble gases?
The basis for Mendeleev's arrangement of the periodic table
What is atomic mass?
Plutonium is an example of this type of element
What is an inner transition metal?
These elements are characterized by electrons filling the f sublevel
What are the inner transition metals?
The energy required to remove an electron from an atom
What is ionization energy?
A cation of Ca2+ has this many electrons
What is 18?
Mendeleev left blank spaces in his periodic table for these two elements
What is Ga and Ge?
Tellurium is an example of this type of element
What is a metalloid?
Element that ends in 4d9
What is Silver (Ag)?
The ability of an atom to attract electrons when the atom is in a compound
What is electronegativity?
This subatomic particle plays the greatest part in determining the properties of an element
What is the electron?
By 1700, scientists had discovered this many elements
What is 13?
Group 1A and Group 7A are examples of this category of elements
What are the representative elements?
The highest occupied s and p sublevels of this group are completely filled
What are the noble gases?
Aluminum (Al) has a smaller this property compared to Sodium (Na).
What is atomic radius?
Of the elements K, Cs, and Br, this element has the greater electronegativity
What is Br?