Atomic Structure Flashcards
Protons have a mass of approximately one ______ ______ _______.
Atomic mass unit (amu)
The atomic number (Z) of an element is equal to the number of ______ found in an atom of that element.
Protons
True or false: Together, the protons and neutrons of the nucleus make up almost the entire mass of an atom.
True. The mass of a single electron is negligible.
What is the mass number (A) of an atom?
The sum of the protons and neutrons in an atom’s nucleus.
What are isotopes?
Atoms of the same element that have the same number of protons but different numbers of neutrons.
Do electrons closer to the nucleus have more or less energy compared to electrons farther away from the nucleus?
Less energy
Generally speaking, which electrons of an atom are involved in chemical bonding?
Valence electrons
A positively charged atom is called a _____; a negatively charged atom is called a(n) ______.
Cation; anion
True or false: The atomic mass of an atom (in amu) is essentially the same as its mass number.
True
The weighted average of different isotopes is referred to as atomic ______. It is the number reported on the periodic table.
Weight
What is the numerical value of Avogadro’s number?
6.02 x 10^23
The _____ state of an atom is the state of lowest energy, in which all electrons are in the lowest possible orbitals.
Ground
An atom is said to be in the ______ state when at least one electron has moved to a subshell of higher than normal energy.
Excited
The group of hydrogen emission lines corresponding to transitions from energy levels n = greater than or equal to 2 to n= 1 is known as the ______ series.
Lyman
The group of hydrogen emission lines corresponding to transitions from energy levels n = greater than or equal to 3 to n= 2 is known as the ______ series.
Balmer
The group of hydrogen emission lines corresponding to transitions from energy levels n = greater than or equal to 4 to n= 3 is known as the ______ series.
Paschen
Describe the Heisenberg uncertainty principle.
This principle states that it is impossible to simultaneously determine both the location and the momentum (energy) of an electron with perfect accuracy.
According to the ______ ______ principle, no two electrons in a given atom can possess the same set of four quantum numbers.
Pauli exclusion
What are the 4 quantum numbers that can be used to completely describe an electron?
- n
- l
- m sub l
- m sub s