1.2- Atomic Structure and The Periodic Table Flashcards
What is the smallest unit of an element?
An atom.
True or False: Atoms are indivisible.
False.
What are the three main subatomic particles?
Protons, neutrons, and electrons.
Where are protons located in an atom?
In the nucleus.
What is the charge of an electron?
Negative.
What is the relative mass of a neutron?
1 atomic mass unit (amu).
Fill in the blank: The atomic number of an element is equal to the number of ________ in its nucleus.
Protons.
What is the mass number of an atom?
The total number of protons and neutrons in the nucleus.
True or False: Isotopes of an element have the same number of protons but different numbers of neutrons.
True.
What is the charge of a proton?
Positive.
What is the electron configuration of a neutral oxygen atom?
1s² 2s² 2p⁴.
Fill in the blank: The nucleus of an atom contains ________ and ________.
Protons; neutrons.
What does the term ‘valence electrons’ refer to?
Electrons in the outermost shell of an atom.
What is the significance of valence electrons?
They determine the chemical properties and reactivity of an element.
Which subatomic particle has a negligible mass?
Electron.
What is an ion?
An atom or molecule that has a net electrical charge due to the loss or gain of one or more electrons.
True or False: Cations are positively charged ions.
True.
What is the electron configuration for sodium (Na)?
1s² 2s² 2p⁶ 3s¹.
Fill in the blank: The maximum number of electrons in the first shell of an atom is ________.
2.
What is the principal quantum number?
It indicates the energy level of an electron in an atom.
What is meant by ‘excited state’ of an atom?
When an electron absorbs energy and moves to a higher energy level.
What is the Pauli Exclusion Principle?
No two electrons in an atom can have the same set of four quantum numbers.
What does the term ‘orbital’ refer to?
A region in an atom where there is a high probability of finding an electron.
What is the shape of an s orbital?
Spherical.
