An atom is the smallest unit of an element that maintains the properties of that element, consisting of protons, neutrons, and electrons.
What is the periodic table?
The periodic table is a tabular arrangement of chemical elements, ordered by their atomic number, electron configuration, and recurring chemical properties.
Who created the modern periodic table?
Dmitri Mendeleev is credited with creating the first periodic table similar to the one in use today.
What is an element?
An element is a substance that cannot be broken down into simpler substances by chemical means.
Define atomic number.
The atomic number is the number of protons in an atom's nucleus and determines the element's identity.
What determines the chemical properties of an atom?
The number of electrons, particularly those in the outermost shell, determines an atom's chemical properties.
What is an ion?
An ion is an atom that has gained or lost one or more electrons, giving it a positive or negative charge.
What are isotopes?
Isotopes are variants of a particular chemical element that have the same number of protons but a different number of neutrons.
Describe the layout of the periodic table.
The periodic table is organized into rows (periods) and columns (groups), with elements ordered by increasing atomic number.
What is a group in the periodic table?
A group is a vertical column in the periodic table and elements in a group typically have similar chemical properties.
What is the significance of Group 1 elements?
Group 1 elements are known as alkali metals; they are highly reactive, especially with water.
What is an electron shell?
An electron shell is the outside part of an atom around the atomic nucleus where electrons are found.
Define valence electrons.
Valence electrons are the electrons in the outer shell of an atom that are involved in forming bonds.
What is a period in the periodic table?
A period is a horizontal row in the periodic table and it indicates the number of electron shells in the atoms of the elements present.
Why do noble gases have stable electron configurations?
Noble gases have stable electron configurations because their outer electron shells are full.