4.2 Flashcards
(7 cards)
1
Q
proton
A
a subatomic particle that has a positive charge and that is found in the nucleus of an atom
2
Q
atomic mass unit
A
a unit of mass that describes the mass of an atom or molecule
3
Q
neutron
A
a subatomic particle that has no charge and that is found in the nucleus of an atom
4
Q
atomic number
A
the number of protons in the nucleus of an atom the atomic number is the same for all atoms of an elemnt
5
Q
isotope
A
an atom that has the same number of protons ( or the same atomic number) as other atoms of the same element do but that has a different number of neutrons (and thus differnt atomic mass)
6
Q
Mass number
A
The sum of the numbers of protons and neutrons in the nucleus of an atom
7
Q
Atomic mass
A
The mass of an Adam express in atomic mass units
