Atomic Structure Flashcards
(21 cards)
What is an atom?
the basic unit of a chemical element
what is an atomic number
the number of protons in the nucleus
The atomic number =
protons in an atom
what is the nucleus
core of an atom containing protons and neutrons
what is the atomic mass of an atom
the atomic weight of an atom
Sodium 11 Na 22.99 What is the atomic mass of Sodium?
23
What is the mass number of an atom?
Mass number is the sum of the protons and neutrons
Protons are
positive, negative, or neutral
Positive
Electrons are
positive, negative, or neutral
negative
Neutrons are
positive, negative or neutral
Neutral
How many neutrons are in? 17 Cl 35.45 chlorine
Mass = 35
- A# = 17
= Neutrons = 18
what is the mass number of 4 Be 9.012 Berylium
9
what is the periodic table?
a display of chemical elements
What type of charge does a proton have?
+ Positive
which two subatomic particles are located in the nucleus of an atom?
Protons and neutrons
what type of charge does a neutron have?
No charge
why are elements on the periodic table placed into groups
because they have similar chemical properties
which group of elements is the most stable
noble gases
what is an ion
an atom or molecule with a net electric charge due to the loss or gain of one or more electrons.
which two characteristics are used to position elements on the periodic table
Atomic number
Number of protons
what type of charge does an electron have
- negative
