Science Flashcards
(25 cards)
Atomic Number
A number of protons in the nucleas
Electron
Negatively charged neutron
Electron cloud
the region surrounding the nucleus
element
a substance that cannot be broken down
Half-life
The time needed for one-half of the mass of the sample
Mass number- The sum of neutrons and protons
electrically neutral particle
Proton
positively charged neutron
radioactive decay
Release of nuclear particles
Transmutation
the changing of an element
Beta-particle
High energy electron
Alpha particle
Two Neutrons and Two protons
Average atomic mass
the average mass of an atom
Atom
the basic unit of matter
what is the particle in the nucleus with no charge?
neutron
The atomic mass of an atom is…..and…..
Protons and neutrons
Where are the electrons in an atom?
outside of the atom.
What did J.J Thomson discover?
Opposites attract
The mass of an isotope is the number of
Protons and neutrons
isotopes are atoms of the same element with the same number of
Protons and Electrons
define the number of neutrons and subtract …..from……
protons from atomic mass
The most stable of isotope of an atom with 12 protons have….neutrons
12
A strong nuclear force holds…..together
Atoms
radioactive decay is the release of…
Atomic nucleus
A……particle consists of two protons and two neutrons
Alpha particles
