Atomic Structure & Basics 1
This number, unique to each element, represents the number of protons in its nucleus.
What is the atomic number?
Elements in Group 18, like Neon (Ne) and Argon (Ar), are called this because they rarely react.
What are Noble Gases?
The elements in the main body of the table are organized by increasing amount of this key atomic characteristic.
What is atomic number?
This subatomic particle has a negative charge and determines the chemical behavior of an atom.
What is an electron?
All elements in the same group have similar chemical properties because they share the same number of these.
What are valence electrons?
Boron (B), Silicon (Si), and Arsenic (As) belong to this class of elements, sharing properties of both metals and nonmetals.
What are metalloids?
These highly reactive elements in Group 1, like Sodium (Na), are never found uncombined in nature.
What are Alkali Metals?
This Russian chemist is widely credited with creating the first recognizable periodic table in 1869.
Who is Dmitri Mendeleev?
The elements Copper (Cu), Silver (Ag), and Gold (Au) are all examples of this general class of elements (excluding metalloids and nonmetals).
What are metals?
Group 16 elements, which includes Oxygen and Sulfur, are sometimes called this family.
What are the Chalcogens?
The total number of protons and neutrons in an atom's nucleus gives you this value.
What is the mass number (or atomic mass)?
Group 17 elements, like Chlorine (Cl), are known for forming salts and are collectively called this.
What are Halogens?
Mendeleev originally organized the table based on increasing atomic mass, which led to a few misplaced elements, but he predicted the existence of elements like Germanium using this technique.
What is a blank space (or prediction)?
Atoms of the same element that have different numbers of neutrons are called this.
What are isotopes?
This specific halogen is a yellowish-green gas at standard temperature and pressure.
What is Chlorine (Cl)?
These are the energy containers where electrons orbit the nucleus.
What are electron shells?
All elements in Group 2, known as the Alkaline Earth Metals, have this specific number of valence electrons.
What is two (2)?
The two rows separated and placed at the bottom of the table are known as the lanthanides and this other series.
What are the actinides?
The group number (1-18) of the main group elements often tells you this number, which relates to bonding.
What are valence electrons?
The element Iron (Fe) belongs to this category of metals that are often used in structural materials and alloys.
What are Transition Metals?
An atom of Potassium (K) typically forms an ion with this charge, achieving a stable electron configuration.
What is +1 (or a cation)?
The name given to the large block of metallic elements found in Groups 3-12, often forming brightly colored compounds.
What are Transition Metals?
Henry Moseley fixed the organization of the periodic table in 1913 by basing the arrangement on this specific value.
What is the atomic number?
An atom of Fluorine (F), with an atomic number of 9, typically gains one electron to form an ion with this symbol.
What is F−?
This element, the only nonmetal in Group 1, is typically placed both above Group 1 and sometimes Group 17 on the table.
What is Hydrogen (H)?