the atom date:. definition of atom: – the basic unit of an element; the building blocks of matter...
TRANSCRIPT
The AtomThe Atom
Date:
• Definition of atom:– The basic unit of an element; the
building blocks of matter– Have no charge– Composed of 3 subatomic particles
Energy levels:These make up the electron cloud
Subatomic ParticlesParticle Symbol Charge Mass
(amu)Location Determines
proton p+ +1 1 nucleus Element identity
neutron no 0 1 nucleus The particular isotope
electron e- -1 0.0005 electron cloud
If an ion
Electrostatic repulsion and attraction
• Opposite charges attract– Electrostatic attraction– Protons and electrons– Keeps the electrons from flying away
• Like charges repel– Electrostatic repulsion– Protons–Why doesn’t the nucleus explode?– The STRONG NUCLEAR FORCE
nucleons
What is the spacing within an atom?
Numbers on the PT
What do they all mean?
Key:
Atomic number, number of protons
Element symbol
Element name
Average atomic mass
The mass calculated by summing the masses of an element's isotopes, each multiplied by its natural abundance on Earth.
Nuclide
C12
6
Name the numbers
and tell what they
mean Mass number:Sum of #p+ and # no
Atomic number:#p+ If an atom, then #e- also
Nuclide
C12
6
How many of each
subatomic
particle?? Mass number:Sum of #p+ and # no
Atomic number:#p+ If an atom, then #e- also
Since the atomic number is 6, there are 6 p+. This is an atom (because there is no charge written in the upper right hand corner) so this atom has 6 e- too! To determine the number of neutrons, subtract the atomic number from the mass number, 12 – 6 = 6 neutrons.
3Li7How many of each
subatomic
particle??
3Li7How many of each
subatomic
particle??
Atomic # = # p+
3p+
3Li7How many of each
subatomic
particle??
3p+
No charge in upper right hand corner, so it is an atom; the number of p+ = # e-
3e-
3Li7How many of each
subatomic
particle??
3p+
Mass number – atomic number = #no
3e-
-
44no
1H3How many of each
subatomic
particle??
How many of each
subatomic
particle??
Atomic # = # p+
1p+
1H3
How many of each
subatomic
particle??
1p+
No charge in upper right hand corner, so it is an atom; the number of p+ = # e-
1e-
1H3
How many of each
subatomic
particle??
1p+
Mass number – atomic number = #no
1e-
-
22no
1H3
6C14How many of each
subatomic
particle??
How many of each
subatomic
particle??
Atomic # = # p+
6p+
6C14
How many of each
subatomic
particle??
6p+
No charge in upper right hand corner, so it is an atom; the number of p+ = # e-
6e-
6C14
How many of each
subatomic
particle??
6p+
Mass number – atomic number = #no
6e-
-
88no
6C14
What do these all have in common?
6C14
6C13
6C12
• They are all C so they all have 6 p+. But they have different mass numbers, meaning they have different #neutrons!
6C14
6C13
6C12
These are Isotopes!• Atoms of the same element that
differ in the # of neutrons
What do these all have in common?
Vocabulary • Atom: the basic unit of a chemical element.• Average atomic mass: The mass calculated by summing
the masses of an element's isotopes, each multiplied by its natural abundance on Earth.
• Electron: a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids.
• Electron cloud: an atom model wherein electrons are no longer depicted as particles moving around the nucleus in a fixed orbit but are free to move anywhere within the cloud
• Energy levels – the various levels (rings) shown around the nucleus of an atom, the number of energy levels an atom has is equal to the period number.
• Ion – atoms with a charge because it has gained or lost electrons• Isotope – two atoms of the same element that differ in the number
of neutrons• Mass number – the sum of protons and neutron, the number of
nucleons present in the nucleus• Neutron – a subatomic particle with no charge found in the nucleus
of an atom• Nucleon – a proton or neutron• Nucleus - the positively charged central core of an atom, consisting
of protons and neutrons and containing nearly all its mass.• Nuclide - An atomic nucleus identified by its atomic element and its
mass number. • Proton – a subatomic particle with a positive charge found in the
nucleus of an atom• Strong nuclear force - one of the four basic forces in nature, this
force holds the nucleus together • Subatomic particle - a particle smaller than an atom
• Paste into notebook• Download A+ spelling
• Type the vocabulary term
• Enter the definitions• Practice daily• Until you know these
terms you will be lost
Homework
• Online quizzes– Elements – both weeks– Read PT– Lab Equipment– Safety– Physical vs Chemical
• Vocabulary• Worksheet on the number of
subatomic particles.