Download Subatomic

Subatomic Particles
particle
symbols
Relative
electric
charge
Mass
number
Relative
mass
(amu)
Actual
mass
(kg)
electron
-1
0
+1
neutron
n0
0
1
1
0.0055
1.007
9.1 x 10-31
proton
ep+
1.008
1.7 x 10-27
The electron
doesn’t
contribute any
significant mass
to the atom.
1.7 x 10-27
Mass number of an atom with:
1 proton
1 electron
1 neutron
= 1 (1.007amu)
= 0 (0.0055 amu)
= 1 (1.008 amu)
2 amu
Atomic number is the number of protons
Mass number is the number of protons + neutrons.
An atom with 6 protons and 7
neutrons has an atomic number of 6
and a mass number of 13.
This atom would be carbon because
carbon’s atomic number is 6.
Isotopes
Isotopes are atoms of the same element with different masses.
Not all atoms of an element are the same.
Not all atoms of hydrogen are the same.
There exists 3 isotopes (types) of hydrogen.
Substitute the word variety (or flavors).
Isotopes of Hydrogen
Isotope
hydrogen-1
Nuclear Number of Number of Number of
Symbol
protons
electrons
neutrons
1
H
1
1
0
hydrogen-2
1
2
H
1
1
1
1
hydrogen-3
3
1
1
2
H
1
mass number=
protons + neutrons
1p+2n
atomic
number= protons
1p
3
H
1
protons + neutrons
6 p + 7n
protons
6p
13
C
6
Isotopes of Hydrogen
Isotope
hydrogen-1
hydrogen-2
Nuclear Number of Number of
Symbol
protons
neutrons
1
H
1
0
1
H
1
1
2
H
1
1
2
3
1
2
1
hydrogen-3
Mass
number
3
Mass number is the number of protons + neutrons.
Ions
(not to be confused with isotope)
Ion is an atom that has either lost or gained electrons
and therefore has a charge. (not neutral)
Cl + e- a Cl-1
S + 2e- a S-2
Ions
Na a Na+1 + e-
Symbol
O
K
K
F-1
Atomic
number
Mass
number
# of
protons
8
17
39
40
19
8
19
19
9
19
19
9
# of
# of
neutrons electrons
9
20
21
10
8
19
19
10
Use the periodic table to find atomic number.
Atomic number = # of protons.
Mass number = # of protons + neutrons
Since the charge is zero, # of protons = # of electrons
charge
0
0
0
-1