Unit 2: Atomic Structure 1 & 2 Flashcards
(70 cards)
What is the maximum number of electrons in an orbital?
An orbital can accommodate a maximum of two electrons with opposite spins.
What does the (n+l) rule indicate about orbital energy?
Lower (n+l) values indicate lower energy orbitals, which are filled first.
Why is understanding electron configuration important?
It helps determine the number of electrons in an orbital and identify sub-shells and principal energy levels.
How do you determine which orbital fills first when (n+l) values are the same?
The orbital with the lower n value has lower energy and fills first.
How many p, d, and f orbitals are there?
There are three p orbitals, five d orbitals, and seven f orbitals.
What are quantum numbers used for in atomic structure?
They describe the characteristics of orbitals, including shape, size, and orientation.
What defines the number of protons in an atom?
The number of protons identifies the element and determines its atomic number.
What is electronic configuration?
The distribution of electrons into different levels, subshells, and orbitals of an atom.
What are the (n+l) values for the 4s and 3d orbitals?
4s: 4, 3d: 5; thus 4s has lower energy than 3d.
When does electron pairing begin in orbitals?
Pairing starts with the 4th electron in p, 6th in d, and 8th in f orbitals.
What defines an atom?
An atom is the smallest unit of an element, composed of a nucleus and electrons.
What is an isotope?
Atoms with the same number of protons but different neutrons and mass numbers.
What does the principal quantum number (n) indicate?
It determines the average distance of an electron from the nucleus.
What are the three main principles of electronic configuration?
Aufbau’s Principle, Pauli’s Exclusion Principle, and Hund’s Rule.
What does Pauli’s Exclusion Principle state?
No two electrons can have the same four quantum numbers; they can share three but differ in spin.
What is the purpose of quantum numbers in relation to electrons?
They describe the position of an electron in an atom, serving as its ‘address.’
What particles make up the atomic nucleus?
The atomic nucleus is made up of protons and neutrons
What are the quantum numbers associated with K-shell electrons?
K-shell electrons have n=1, l=0, m=0, and s=+1/2 or -1/2.
What distinguishes isobars from isotopes?
Isobars have different atomic numbers but the same mass number.
How many orbitals are in an s subshell?
There is 1 orbital in an s subshell.
How is the maximum number of electrons in a shell calculated?
The maximum is calculated using the formula 2n².
List the electronic configuration for Calcium.
Calcium: 1s² 2s² 2p⁶ 3s²
What is the charge and location of electrons?
Electrons are negatively charged particles located in shells around the nucleus.
What are the possible values of the spin quantum number (s)?
+1/2 (clockwise) and -1/2 (anticlockwise)