2.2.1 - Electron Structure Flashcards
What is the electron configuration of an atom?
Electron configuration describes the arrangement of electrons in an atom’s orbitals, from the lowest to the highest energy level.
How are electrons arranged in an atom?
Electrons are arranged in shells or energy levels around the nucleus. Each shell can hold a specific maximum number of electrons.
What is the maximum number of electrons that can be held in a given shell?
The maximum number of electrons in a shell is 2n², where n is the number of the shell. For example, the first shell (n=1) holds 2 electrons, the second shell (n=2) holds 8 electrons, etc.
What are orbitals?
Orbitals are regions of space around the nucleus where an electron is likely to be found. Orbitals come in different shapes: s (spherical), p (dumbbell-shaped), d, and f.
How many electrons can each orbital type hold?
- s-orbital: 2 electrons
- p-orbital: 6 electrons (3 orbitals, 2 electrons per orbital)
- d-orbital: 10 electrons (5 orbitals, 2 electrons per orbital)
- f-orbital: 14 electrons (7 orbitals, 2 electrons per orbital)
What are the energy levels of electrons?
Energy levels refer to the specific distances from the nucleus where electrons are most likely to be found. These are sometimes referred to as shells and are denoted by the quantum number n.
What is the Pauli exclusion principle?
The Pauli exclusion principle states that no two electrons in an atom can have the same set of quantum numbers. In an orbital, only two electrons can exist, and they must have opposite spins.
What is Hund’s rule?
Hund’s rule states that when electrons occupy orbitals of equal energy (degenerate orbitals), they will fill each orbital singly before pairing up. This minimizes repulsion and maximizes stability.
What is the ** Aufbau principle**?
The Aufbau principle states that electrons fill orbitals starting from the lowest energy level and move to higher energy levels only after the lower ones are filled.
How is the electron configuration of an atom written?
The electron configuration of an atom is written by indicating the number of electrons in each orbital or subshell. For example, the electron configuration of oxygen (O) is 1s² 2s² 2p⁴.
What is the electron configuration of sodium (Na)?
The electron configuration of sodium (Na) is 1s² 2s² 2p⁶ 3s¹.
What is the noble gas notation for an element’s electron configuration?
Noble gas notation is a shorthand way of writing electron configurations by using the symbol of the nearest noble gas to represent the inner core electrons. For example, Na: [Ne] 3s¹.
What is the electron configuration of chlorine (Cl)?
The electron configuration of chlorine (Cl) is 1s² 2s² 2p⁶ 3s² 3p⁵.
What is the electron configuration of carbon (C)?
The electron configuration of carbon (C) is 1s² 2s² 2p².
How do you determine the number of electrons in an atom?
The number of electrons in a neutral atom is equal to the atomic number of the element. For example, carbon has an atomic number of 6, so it has 6 electrons.
What is the atomic orbital?
An atomic orbital is a region within an atom where there is a high probability of finding an electron. Orbitals have different shapes (s, p, d, f) and hold a specific maximum number of electrons.
What is the principle quantum number (n)?
The principle quantum number (n) defines the energy level of an electron in an atom. It is a positive integer (1, 2, 3, …) that indicates the relative distance from the nucleus.
How do subshells relate to electron configuration?
Subshells are divisions of electron energy levels (shells). For example, the second energy level (n=2) contains the 2s and 2p subshells. Each subshell consists of orbitals with specific shapes and electron capacities.
What is the electron configuration of neon (Ne)?
The electron configuration of neon (Ne) is 1s² 2s² 2p⁶, with 10 electrons in total.
What is the shape of an s-orbital?
The shape of an s-orbital is spherical. There is one s-orbital in every energy level, starting from n=1.
What is the shape of a p-orbital?
The shape of a p-orbital is dumbbell-shaped. There are three p-orbitals in each energy level starting from n=2.
What is electron spin?
Electron spin is a property of electrons that describes their angular momentum. Electrons in the same orbital must have opposite spins (one spin-up and one spin-down).
How does the Pauli exclusion principle affect electron arrangement?
The Pauli exclusion principle ensures that no two electrons in an atom can have the same set of quantum numbers, which means each orbital can hold a maximum of two electrons with opposite spins.
What is the periodicity in electron configuration?
Periodicity refers to the recurring pattern in the electron configuration across periods in the periodic table. As you move across a period, electrons fill orbitals in a predictable order based on the element’s atomic number.
How do you predict the chemical behavior of an element using its electron configuration?
The chemical behavior of an element is largely determined by the arrangement of electrons in its outermost shell (valence electrons). The number of valence electrons influences how an element bonds and reacts with other elements.
