Basic atomic Structure Flashcards
What are the 3 subatomic particles of an atom?
protons
- (positive (+) charge)
- mass = 1
Neutrons
-(neutral (0) no charge)
- mass = 1
Electrons
-(negative (-) charge)
- mass = 0
What are the parts of an atom?
An atom has a central nucleus
- it contains protons (+) and
neutrons (0)
Surrounding the central nucleus
- a electron cloud, that
contains shells/energy
levels with electrons (-) on
them.
- these electrons (+) stay on
the shells outside of the
nucleus by their
attraction to the protons
(+) in the nucleus.
What are isotopes?
Atoms that are of the same element but with a different number of neutrons.
Example:
Carbon atoms atomic mass
6 protons + 6 neutrons = 12 atomic mass
Isotope of Carbon atomic mass
6 protons + 7 neutrons = 13 atomic mass
Note:
The carbon atom will always have 6 protons and will never change.
The carbon atom changes to an Isotope of Carbon when the number of neutrons change.
What is the atomic mass of an atom?
It is the sum of the mass of the protons and neutrons in one atom of an element.
protons + neutrons = atomic mass
What is the atomic number?
The number of protons in the nucleus,
whic is also equal to the number of electrons surround the nucleus.
Note:
The number of protons gives you the number of electrons surrounding the nucleus of that atom
of protons = # of electron
Example:
An atom of Iron has an atomic number 26.
That means an atom of Iron has 26 protons.
If the # of protons is always equal the the # of electrons.
Than an atom of Iron also has 26 electrons.
What are neutral atoms?
atoms that have an equal number of protons and electrons.
- charge of (0) neutral
What are Ions?
atoms with a positive or negative charge.
Anions
- a type of ion
- when electrons are gained by an
element they become (-) negatively
charged.
- atoms with Valence #’s greater than
4, will gain electrons.
- Group # greater than 4
- usually (non-metals)
Cations
- a type of Ion
- when electrons are lost, or donated
by an element they become (+)
positively charged.
- atoms with valence #’s less than 4,
lose electrons.
- Group # less than 4
- usually (metals)
What are Ionic bonds?
Its when oppositely charged Ions attract one another, and transfer electrons between atoms, creating a bond.
They contain ionic compounds that are soluble in water and conduct electricity
Example:
Na Sodium - is soluble in water
Cl Chlorine- is electricity conductor
They become NaCl Sodium Chloride
Na is located at group 1, period 3, meaning it has 3 energy shells and allowed 1 electron in the outer shell.
Cl is located at group 7, period 3, meaning it has 3 energy shells and allowed 7 electrons in the outer shell.
Na donates 1 electron making it positive and Cl gains 1 electron making it negative.
Together they have formed an ionic bond becoming
NA+Cl-
Na know has no electron in its outer shell completing it and Cl has 8 elctrons in the outer shell completing it.
It is easier to gain or lose a smaller number to be complete, this will determine whether the atom will gove electrons or gain electrons.
Explain the Periodic table labels?
The atomic number = total number of protons
The atomic number = total number of electrons surround the atoms nucleus
Atomic mass= is shown as decimal and is
the sum of protons plus neutrons.
- so you can delete the atomic
number from the atomic mass
to find the number of neutrons.
- atomic mass - atomic # = # of neutrons Group # =# of Valence (bonding) electrons - valence electrons -are how many electrons are suppose to be in the last and outermost orbital energy shell. - ignore the transition metal section - group # 1 through 8 - group 1-2 ends at the beginning of the transition metal section. - group 3-8 begins at the end of the transition metal section.
Period # = # of orbital shells or energy
levels that hold electrons.
- each level holds a different
amount of electrons per level.
- Periods represent large
electron “highways” with
multiple orbital “lanes”.
Example- period 1 - hold 2 electrons period 2 - hold 8 electrons period 3 - hold 18 electrons period 4 - hold 32 period 5 - hold 50 period 6 - hold 72 period 7 - hold 98
Chemical symbol- symbol or Abreviation of
that element or atom
Element name - full name of the atom or
element.
What are Nobel gases and why don’t they react with other atoms?
It is inert gas
Examples. Helium, Neon
They have full valence shells and are quite stable
They wont react with other atoms because they are so stable.
Covalent Bond
When atoms share electron pairs to achieve stability.