What is the atomic number and expected ground-state electron configuration of the yet undiscovered element directly below Fr in the periodic table?

Verified step by step guidance

1. Identify the position of Francium (Fr) on the periodic table. Francium is located in Group 1 and Period 7.
2. Determine the position of the element directly below Francium. This element would be in Group 1 and Period 8.
3. Calculate the atomic number of the new element. Since each period adds a new principal quantum number (n), and Group 1 elements increase their atomic number by 1 as you move down the group, add 32 to the atomic number of Francium (which is 87) to account for the new period.
4. Predict the electron configuration of the new element. Start with the electron configuration of Francium, [Rn]7s1, and then add electrons corresponding to the next period. This involves filling the 8s orbital.
5. Write the expected ground-state electron configuration for the new element, considering that it will follow the same pattern as other alkali metals, filling the s-orbital of the highest principal quantum number.

Key Concepts

Atomic Number

The atomic number of an element is defined as the number of protons found in the nucleus of its atoms. It determines the element's identity and its position in the periodic table. For example, francium (Fr) has an atomic number of 87, meaning it has 87 protons. The element directly below francium would have an atomic number of 88.

Electron Configuration

Electron configuration describes the distribution of electrons in an atom's orbitals. It follows the Aufbau principle, which states that electrons fill the lowest energy orbitals first. For the element below francium, which is expected to be radium (Ra), the ground-state electron configuration would be [Rn] 7s², indicating that it has two electrons in the outermost s orbital.

Periodic Table Trends

The periodic table exhibits trends in atomic properties, including atomic size, ionization energy, and electron affinity. Elements in the same group, like francium and the undiscovered element below it, share similar chemical properties and electron configurations. Understanding these trends helps predict the behavior of elements based on their position in the periodic table.