Chapter 2- A particle view of matter Flashcards
(22 cards)
What is a proton?
Positively charged particle.
What is a neutron?
Particle with no charge.
what is an electron?
Negatively charged particle.
What is the scientific model?
Description that scientists use to represent the important features of what they are trying to describe.
Where is most of the mass on an atom located?
Nucleus
what are alpha particles?
Small, positively charged particles emitted by atoms of radioactive decay.
What two kinds of particles are found in the nucleus?
Protons
Nuetrons
What is a cation?
Positively charged ion.
What is an anion?
Negatively charged ion.
What is an isotope?
An atom with the same atomic number but different mass number (varieties of a particular element).
What is the atomic number?
Number of protons in the nucleus of an atom.
What is the mass number?
Total number of protons and neutrons
What is an ion?
A charged particle produced when an atom loses or gains an electron.
How many electrons can these shells fit: Shell 1? Shell 2? Shell 3? Shell n?
Shell 1- 2 electrons
Shell 2- 8 electrons
Shell 3 - 18 electrons
Shell n- 2n squared electrons
What is the exception to the number of electrons a shell can fit?
No shell will contain more than 8 electrons until there are at least 2 electrons in the following shell.
What is a valence electron?
Electron in the outermost shell of an atom.
Define: Orbital
regions of space in which electrons move
Define: Shell
A region in which a group of electrons of similar energy levels moves about the nucleus.
Define: Subshell
Energy levels of similar energy within shells.
How many subshells in each shell?
Same as the number of shells
E.g. Shell 1, 1 subshell, Shell 3, 3 subshells
Define: Ground state
When the electrons of an atoms are in the lowest energy state possible.
Define: Excited state
The state of an atom, ion, etc in which one or more electrons have absorbed energy and are not in their lowest energy levels.
