Question

Write electron configurations for the following metals. a. Ni b. Cd c. Zr d. Os

Short answer

The electron configurations for the given metals are as follows: a. Ni: \( 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^8 \) b. Cd: \( 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5s^2 4d^10 \) c. Zr: \( 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5s^2 4d^2 \) d. Os: \( 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5s^2 4d^{10} 5p^6 6s^2 4f^{14} 5d^6 \)

Step-by-step solution

Understand electron configuration notation

Electron configuration notation is a shorthand way to represent the distribution of electrons among the atomic orbitals. It consists of the energy level, the type of orbital (s, p, d, or f), and the number of electrons in that orbital as a superscript. For example, a configuration of 1s^2 indicates that there are 2 electrons in the 1s orbital. The order in which orbitals fill is given by the Aufbau principle.

Recall the order to fill orbitals

To write electron configurations correctly, we must recall the order in which orbitals fill as per the Aufbau principle. The filling order is: 1s > 2s > 2p > 3s > 3p > 4s > 3d > 4p > 5s > 4d > 5p > 6s > 4f > 5d > 6p > 7s > 5f > 6d > 7p

Find the atomic numbers of the metals

Using the periodic table, we can find the atomic numbers of the given metals: a. Ni (Nickel) - Atomic number 28 b. Cd (Cadmium) - Atomic number 48 c. Zr (Zirconium) - Atomic number 40 d. Os (Osmium) - Atomic number 76

Write the electron configurations for the metals

Following the aufbau principle, we will write the electron configurations for the metals with given atomic numbers: a. Ni (Nickel, atomic number 28) - \( 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^8 \) b. Cd (Cadmium, atomic number 48) - \( 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5s^2 4d^10 \) c. Zr (Zirconium, atomic number 40) - \( 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5s^2 4d^2 \) d. Os (Osmium, atomic number 76) - \( 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5s^2 4d^{10} 5p^6 6s^2 4f^{14} 5d^6 \)

Key concepts

Aufbau Principle

The Aufbau Principle is a fundamental concept in chemistry that helps us understand how electrons are distributed in an atom's orbitals. "Aufbau" is a German word that translates to "building up," which signifies electrons filling the lowest energy orbitals first before moving on to higher energy orbitals. This principle is crucial for predicting the electron configurations of atoms.
For example, using the Aufbau Principle, we can determine why the 1s orbital fills before the 2s, or why the 5s fills before the 4d. As electrons occupy the lowest available energy states first, they fill in a specific order, which is dictated by their energy levels and is crucial for determining the chemical properties of an element.
When writing electron configurations for elements, the Aufbau Principle helps ensure that we start filling electrons from the lowest energy level and work upwards. This is essential for accurately predicting the arrangement of electrons around the nucleus of an atom.

Atomic Orbitals

Atomic orbitals are regions within an atom where electrons are most likely to be found. These orbitals come in different shapes and sizes, which are typically designated as s, p, d, and f. Each type of orbital has a unique shape, impacting how electrons fill these spaces.

• s-orbitals: Spherical in shape, they can hold up to 2 electrons.
• p-orbitals: Dumbbell-shaped, each set can hold 6 electrons (2 in each of the three orbitals).
• d-orbitals: More complex in shape, each set can hold 10 electrons.
• f-orbitals: Even more complex, each set can hold 14 electrons.

The arrangement and filling of these orbitals are key to understanding an atom's electron configuration. The orbitals determine how electrons are distributed in an atom and are foundational for predicting the chemical bonding and reactivity of elements.
Each orbital has specific energy levels, and electrons will start filling the lower energy orbitals first, as dictated by the Aufbau Principle, moving to higher ones as lower energy levels are filled.

Periodic Table

The Periodic Table is an organized chart of elements arranged by increasing atomic number. Its layout provides valuable information about elements’ chemical properties and their electron configurations.

• The table is divided into blocks (s, p, d, f) that indicate which orbitals electrons are filling.
• The rows, called periods, show the sequential additions of electrons to different orbital shells.
• Columns, known as groups, contain elements with similar electron configurations and chemical properties.

Transition metals, for example, are found in the d-block of the Periodic Table. Their electron configurations are influenced by partially filled d-orbitals, giving them unique characteristics and diverse oxidation states.
Understanding the placement of elements on the Periodic Table allows students to deduce electron configurations, predict element behavior in chemical reactions, and explore trends across different element groups, such as reactivity and atomic size.

Transition Metals

Transition metals are elements that occupy the d-block of the Periodic Table and include metals like nickel (Ni), cadmium (Cd), and osmium (Os). These elements are known for several distinctive characteristics.

• They usually have partially filled d-orbitals.
• They exhibit multiple oxidation states, which influence their chemical reactivity.
• Transition metals often form colored compounds and are known for their catalytic properties.

The electron configuration of transition metals can sometimes be tricky because d-orbitals fill after the s-orbitals of the next highest energy level (for example, the 4s orbital fills before the 3d). This affects the metal's chemical properties, including its magnetic and conductive behaviors.
Studying transition metals enhances understanding of advanced chemistry concepts and is vital for applications involving material science and industrial catalysts.