High School

How do you determine core electrons, valence electrons, and unpaired electrons from the periodic table?

A. Subtract the atomic number from the group number for core electrons, look at the group number for valence electrons, and count unpaired electrons in the electron configuration.
B. Add the atomic number and group number for core electrons, look at the period number for valence electrons, and count unpaired electrons in the electron configuration.
C. Subtract the atomic number from the period number for core electrons, look at the group number for valence electrons, and count unpaired electrons in the electron configuration.
D. Add the atomic number and period number for core electrons, look at the period number for valence electrons, and count unpaired electrons in the electron configuration.

Answer :

Final answer:

Core electrons are calculated by subtracting valence electrons from the atomic number. Valence electrons are generally represented by the group number, and unpaired electrons are counted within the electron configuration.

Explanation:

To determine the core electrons, valence electrons, and unpaired electrons from the periodic table, you generally follow the following steps:

  • Core Electrons: These are the electrons in an atom that are not valence electrons and don't participate in bonding. Core electrons are essentially the total number of electrons minus the valence electrons. Therefore, you can calculate them by subtracting the number of valence electrons from the atomic number.
  • Valence Electrons: For the most part, the group number on the periodic table (ignoring any transition metals) typically indicates the number of valence electrons.
  • Unpaired Electrons: These can be determined by writing out the electron configuration of an atom. Any orbitals that contain only one electron have an unpaired electron.

Learn more about Periodic Table here:

https://brainly.com/question/19622011

#SPJ11

To determine core, valence, and unpaired electrons in an atom, one must examine the electron configuration and the periodic table's group number. Valence electrons correspond to the outermost shell and can often be inferred from the group number for main group elements, while core electrons occupy the inner shells. Unpaired electrons are counted by inspecting the electron configuration's outermost subshells.

To determine core electrons, valence electrons, and unpaired electrons from the periodic table, you would need to consider the electron configuration of an atom, which can be deduced from its position on the periodic table. Incorrect option A refers to subtracting the atomic number from the group number, having no connection to finding core electrons; the correct approach is to look at the electron configuration. Valence electrons are indeed reflected by the group number for main group elements; however, unpaired electrons can only be counted accurately in the electron configuration.

For example, carbon has the electron configuration 1s²2s²2p², which tells us that it has 4 valence electrons (2s²2p²) and 2 core electrons (1s²). Unpaired electrons are those in the valence shell that do not form pairs, as seen with carbon's 2p electrons. In the case of transition metals and other elements, special attention must be given to their specific electron configurations, as the counting method can vary.

For clarity, core electrons are those within inner shells and valence electrons are in the highest-numbered or outermost shell. The group number in the periodic table often helps ascertain the number of valence electrons for main group elements, while transition metals have to be treated case by case. Counting unpaired electrons requires inspecting the electron configuration, particularly the outermost subshells to see which electrons do not have a paired spin.