Mass Number
12 protons, 14 neutrons
What is the mass number?
26
28 protons, 32 neutrons
What is the atomic number?
28
Define an atom.
The smallest unit of matter with unique characteristics.
What are the three subatomic particles?
protons, neutrons, and electrons
How do you determine the charge of an atom?
By subtracting the number of electrons from the number of protons.
3818 Ar
What is the mass number?
38
179 F
What is the atomic number?
9
Define the nucleus of an atom.
The center of the atom containing protons and neutrons.
What is the charge of each subatomic particle?
protons +
neutrons =
electrons -
What charge does a cation have? An anion?
Cation = positive
Anion = negative
How to solve for mass number?
protons + neutrons
Can the number of protons in an atom change?
NOOOOOO no no no no no NO
Define an element.
A substance consisting only of atoms with the same number of protons.
How do you determine the number of protons in an atom?
By using the atomic number off the periodic table.
How do cations and anions get their charge?
Cations have less electrons than protons; anions have more electrons than protons.
What is the mass number for a stable carbon atom?
12
Look at the whole number on the periodic table.
Define an ion.
An atom, or group of atoms, that are positively or negatively charged due to a change in the number of electrons.
How do you determine the number of neutrons in an atom?
By subtracting the number of protons from the mass number. If no mass number, then assume neutrons are equal to protons.
In general, what charge do metals have? Nonmetals?
Metals = positive
Nonmetals = negative
How many neutrons in Antimony-122?
71
What is the atomic number for the largest alkaline earth metal?
88
Define an isotope.
An atom with a different number of neutrons than protons, causing a change in the mass number.
How do you determine the number of electrons in an atom?
By subtracting the charge from the number of protons. If no charge is provided, assume the electrons are equal to the protons.
Solve the following charges:
12 protons, 10 electrons
15 protons, 18 electrons
36 protons, 36 electrons
+2
-3
0