The Electron Configuration Practice Problems
Following the aufbau principle, identify the orbital filled after the orbitals listed below:
Following the aufbau principle, identify the atomic number with a completed 8p orbital.
Identify the symbol, provide the condensed electron configuration, and draw the orbital diagram for heaviest naturally occurring element.
Identify the symbol, provide the condensed electron configuration, and draw the orbital diagram for the alkali metal in period 4.
Referring to the periodic table, predict the atomic number (Z) and ground-state electron configuration of the unknown element directly below Ra.
Provide the complete electron configuration of nihonium (Z = 113), a newly discovered element.
Among the following subshells, 3d, 4s, 4p, 4d, 4f, 5s, 5p, and 5d, which contain the outermost electrons in a selenium atom?
Draw an orbital-filling diagram for the element of atomic number 28. Use up and down arrows to show electrons. To represent the inner-shell electrons use the symbol of the preceding noble gas.
Arrange the orbitals of an He+ atom in order of decreasing energy: 1s, 2s, 2p, 3s, 3d. Use "=" sign for equal energy level orbitals
Consider the orbital diagrams below that could represent the electron configuration of carbon. Only one of them represents the correct configuration for a carbon in its ground state. Identify the correct configuration.
Naturally occurring neodymium is composed of 5 stable isotopes, 142Nd, 143Nd, 145Nd, 146Nd, and 148Nd. Write the electron configuration for neodymium.
Which of the following elements will have an nd10 (n = 3, 4, 5...) electron configuration as a cation with +2 charge?
Zn, Fe, Cd, Pt
Ce-141 is a radioactive isotope of cerium. It undergoes beta decay to form Pr-141, an isotope of rare-earth metal praseodymium. Write an electron configuration for a Pr-141 atom. Is there something surprising in its electron configuration?
The following diagram shows two probable electron configurations for a X atom:
If a strong magnetic field is absent, is there a difference in the energies of the two configurations? If yes, which one has higher energy?
The energies of the 2s and 2p orbitals for the hydrogen atom are the same. If an electron is added to a hydrogen atom to form a hydride anion, would the energies of 2s and 2p orbitals still remain the same?
Which one of the following electron configurations for fluorine violates the Pauli exclusion principle?
The following diagram below is an approximation of subshell energies for the neon atom. Note the number of orbital or the number of electrons is not shown. A neon lamp is constructed using two electrons enclosed in a glass shell that is filled with 99.5% neon gas at a pressure of 1-20 torr. When electricity is passed through the lamp, an electron is excited to a higher energy level. Photons of light are released when the electron falls back to its original energy level. Identify which energy levels are involved in this process.
For each of the following elements, provide the complete electron configuration.
The following four elements belong to the second and third periods of the periodic table. Draw a complete orbital diagram for each of these elements.
Using the periodic able, provide the name of the element in the fifth period that has fully-filled s and d orbitals.
Using the periodic table, identify the element that is in the fourth period and has five 3d electrons.
Identify which corresponds to the chalcogen group from the following valence electron configurations.
Identify which corresponds to an alkali metal from the following valence electron configurations.
Identify which corresponds to an alkaline earth metal from the following valence electron configurations.
Identify which corresponds to a halogen from the following valence electron configurations.
The following Lewis diagram is for a main group element in the 6th period. What is the electron configuration of the element?
Identify the valence shell electron configuration for the following element groups:
Which one of the following orbital diagrams shows the aufbau principle being violated?
Which one of the following electron configurations represents a violation of the Hund's rule?
For the orbital diagram below, write a full electron configuration. Assuming that the electron configuration describes a neutral atom, name the element.
A neutral atom has the following electron configuration: 1s22s22p63s23p2. What is the chemical symbol for the atom? How many electrons does the atom have? How many 1s electrons are in the atom?
Based on the periodic table, what is the name of the element located in the sixth period that has two 6s electrons and no 5d and 6p electrons?