Download 10) What do we call a highly ionized gas.

CHEMISTRY
Science may have found a cure for
most evils; but it has found no
remedy for the worst of them allthe apathy of human beings.
--Helen Keller
Matter
Anything that has mass and
takes up space.
Atoms
Fundamental building
blocks of all states of
matter.
Smallest particle of an
element that retains the
properties of that
element.
So…What are Atoms made of then?
Phases and Transitions of Matter
What are they?
How many are there?
Solid (Ice Cube)
This phase of matter has a definite
shape and a definite volume.
What about the molecules?
Do they have any energy?
YES!
Though it may not seem like it, at the atomic or
molecular level, the particles shake or vibrate rapidly in
a compact space.
Can we change
this energy
level?
Melting
This is the transition from a ____________ phase of matter to a
___________ phase of matter.
Molecularly, how does this happen?
ADD heat energy to excite
the particles. Creates enough
separation for particles to
slide past one another.
Liquid
This state of matter has a definite volume,
but no definite shape. It takes the shape of
its container.
What about the molecules?
Particles have more energy than its solid form, breaking down any
organization and allowing room for particles to flow past one another.
This is liquid nitrogen
being used to make
ice-cream.
N melts at –210ºC and
freezes at -252 ºC .
Evaporating
This is Review from
weather.
This is the transition from a
____________ phase of matter to
a ___________ phase of matter.
Molecularly, how does this happen?
ADD heat energy to excite
the particles further. Creates enough
separation for particles to completely
separate from the original source.
Boiling
Heating liquid to the point at
which it begins to evaporate.
Turning over of liquid due to
heating it to its evaporation point.
This state of matter has the volume of
the container it is placed it, but no
definite shape. It also takes on the
shape of its container.
What about the molecules?
Particles have more energy
than its solid and liquid form,
allowing them to escape with
high levels of energy as a
vapor.
Gas
What happens if we continue to ADD heat energy?
The further expansion of the gas. Makes it less
dense than the air around it.
OR
Ionize the particles creating…
Plasma
Difficult to
contain due to the
highly ionized
particles. Use
magnets to keep
from touching
other surfaces.
Deionization
To reverse the process, a plasma
must lose its charge and become a
neutral gas again.
How can this Happen?
Gas
Condensing
This is the transition from a
____________ phase of matter to
a ___________ phase of matter.
Molecularly, how does
this happen?
Reverse the
energizing process.
Liquid
This is the transition from a
____________ phase of matter to
a ___________ phase of matter.
Molecularly, how
does this happen?
Freezing
Reverse the
energizing
process.
Solid
Sublimation & Deposition
Solid to Gas
Gas to Solid
This transition only takes into consideration
two states of matter.
When these two
changes occur, they
completely skip the
liquid phase.
Sometimes, “sublimation” is
used to describe both
changes.
8)
Review
Molecules are disconnected and highly energized.
1)
4)
7)
Molecules are able to slide past one another.
2)
5)
6)
Molecules are tightly packed and organized.
10) What do we call a
highly ionized gas.
3)
9)
KMT
Kinetic Molecular Theory
K – Kinetic – energy of doing work
M – Molecular – molecules: tiny structures made up of 2 or more
atoms of the same or of different elements.
T – Theory – Not a Law (so not set in scientific stone), however,
it is the most widely used theory of matter structure and change
Does it always have to be a complete phase change?
NO!
When you wash your hands do you use Hot? Or Cold?
Heat
Can have an abundance…
…a balance…
…or a lack
thereof.
A form of energy that is transferred by a difference in temperature.
What can it do?
Thermal
Expansion
Other than a herd of elephants, how do cracks form in sidewalks?
Ball and Ring
Bimetal Strip
Temperature
Viscosity
Measure of a liquid’s
resistance to flow
Less
More Viscous = ____________
fluid
WHY?!
More
Less Viscous = _____________
fluid
The energy of the molecules.
Think Maple
Syrup
Can we then increase or
decrease a fluid’s level of
viscosity?
Pressure
What happens to a substance when
this is applied?
Solid
Why will a solid
steel ball bounce off
a sidewalk?
Liquid
Gas
What are the
“bends”?
Decompression Sickness
Next Slide
The volume of a fixed amount of gas (at a constant temperature) is
inversely proportional to the gas pressure.
Example Inverse Proportion: Inverse of 2 is ½
So we could say:
Boyle’s Law
1) More pressure
leads to Less
volume
2) Less pressure
leads to More
volume
Demo
Charles’ Law
So we could say:
At constant pressure, volume
of a gas is directly proportional
to temperature.
1) Higher temps lead
to Higher volume
•
Lower temps lead
to Lower volume
Theoretical temperature at
which all molecular movement
would cease.
Absolute Zero
Huh?
Means all that moving and
shaking we talked about with
solids would actually stop. No
motion. No e- clouds.
Nothing.
Has Never Actually Been Achieved!
Heat always seems to find
a way. Heat is energy.
Kinetic energy is therefore
generated.
Superconductivity!
Review
1)
What is the theory widely accepted for explaining the transitions from one state of matter to
another at the atomic level?
2)
What is a form of energy that is transferred by a difference in temperature.
3)
In the ball and ring experiment:
a)
What happened when the ball was heated?
b)
What happened when the ball was cooled?
4)
How do the answers to #3 explain cracks in a sidewalk?
5)
True of False. Temperature scales are only different in name.
6)
By heating a liquid, does it become More or Less viscous?
7)
According to Boyle’s Law, when pressure is ________________, the volume of a gas is
decreased.
8)
According to Charles’ Law, when the temperature of a gas is increased, the volume of space the
gas can fill ________________.
9)
What do we call the theoretical temperature at which all molecular/atomic movement would
cease?
Bonus: What is an explanation as to why this temperature is theoretical?
Elements
Basic materials that create molecules, compounds, mixtures, etc…
These are the most basic materials known. They cannot be broken
down into anything but the atomic particles that define them.
ELEMENTal Questions
Get it…element-al. Element. Get it.
1) How many elements do we know of ?
2) Are they all naturally occurring?
3) How are they different?
Answers
1) 117 have been observed as of 2008
2) No.
92 are naturally occurring, however the rest are synthetically
produced. Often this happens during nuclear reactions.
3) You tell me.
Dalton
Rutherford
Early Models
Thompson
Louis de Broglie
Atoms
These tiny particles are the building blocks
of all matter. They are the smallest material
that can exist and still retain the properties
of what it is they make up.
The three particles of an atom:
1) Proton
2) Neutron
3) Electron
Proton
These Positive particles are found
in the nucleus of the atom.
They have an atomic mass unit
(amu) of 1.
They are the identifiers of each
element in the periodic table.
They are made up of smaller
particles called quarks. Though this
is known, it is still vague as to how
the quarks combine to create (if
they even do) the positive charge of
the proton.
Neutron
Is Neutral.
In the
Nucleus.
Neu-Neu-Nu!
Neutrons are sub-atomic particles that carry no net charge. They
too are equal to a mass of 1 amu, and are also found in the
nucleus. Like protons they are made up of quarks, however the
combination does not seem to create a charge. They play a key
role in finding the atomic mass and defining isotopes.
Nucleus
Center of an atom that
contains particles that
make up the atomic mass.
Protons and neutrons stay
together as a central mass.
This central mass is responsible
for keeping the electrons in orbit
around it.
Electron
Orbit
There are several
layers of electrons
around the nucleus.
Why? Why can’t
they all just move
around at random?
Electron Energy Levels
Each level can contain only a specific maximum amount of electrons.
They can hold less, and shells without electrons may reduce in size. An
atom could lose all electrons, but it would not really be considered an
atom if it lost all of its electrons.
Why does the letter designation start with the letter K?
Valence Electrons
These are the electrons found in the outermost energy level of an
atom. They are responsible for the giving, taking and sharing of
electrons which cause chemical reactions to take place.
The ability for these to be gained or lost is relevant to the
proximity to the nucleus.
Review
1) What do elements help to make up?
2) What are the elements made up of? (1 word, 5 letters)
3) What are the 3 particles that make up the answer to #2?
4) What are their charge properties?
5) What are their locations in the answer to #2?
6) How are the particles on the outside of answer #2 arranged?
7) What do we call the particles responsible for chemical
reactions. (2 words)
8) Why are these reactions important? (1 sentence)
Organized table of elements known to us that exist in the Universe.
Some are gasses, some are liquids, most are solids (metals).
Some are explosive, some are pretty, some are poisonous, some are
useful.
Some we find in nature, some we extract from natural things, some
we make ourselves.
When combined, there becomes an infinite list of creations that we
enjoy, eat, study, take for granted, run into, cut down,
grow…hopefully that is enough and you get the point.
How do we make sense of such simple, yet complex materials?
Periodic Table
Look around the room. Are they different?
Dmitri Mendeleev
First to create a feasible means of organizing the
elements. Allowed for the discovery of unknown (at
the time) elements by using the atomic masses.
Chemical
Symbols
When officially recognized as an element a symbol of 1 or 2 letters is used. One
is always capitalized, and if a second letter is used it will be lower case. 3 letters
are assigned as a element is being studied. The names and symbols represent
Latin name of the element number.
Atomic Number
This is the number that
identifies one unique
element from another.
When looking at the periodic table, you will
typically see this number above the symbol.
However, you should always check to
see if this is true by looking for the
smaller number. Except for Hydrogen,
the Atomic numbers of elements are
always less than the Atomic mass.
Atomic Number = Number of Protons in the Nucleus
The weight or mass of an
atom of an element
calculated by the sum of
the particles of the
nucleus.
What are the
particles of the
nucleus?
Protons + Neutrons = Atomic Mass
Atomic Mass
Atomic Equations
Ok…here are some equations I will expect
you to know and know how to use.
1) Atomic # = # of P+
2) At. Mass = Protons + Neutrons
3) At. Mass – Atomic # = Neutrons
4) At. Mass – Neutrons = Atomic #
5) In equilibrium the #P+ = #e-
Group/Family
Number
Groups are signified by
both numbers and letters.
The A group tells you the
number of valence e-.
Easier to count. You
just count the
columns. Can still tell
you the number of
valence e-.
Do you see the
pattern?
Group and family number will not tell you how many electrons are
in all the shells. So what do we do?
2n²
Ion
What happens
when electrons are
lost or gained?
Atom becomes charged either
_________or _________.
So what are
these ones?
Charge
Reactions
By now, you should
know this, but do you
know its importance as
far as Chemistry is
concerned?
These are the rows
Go left to right
.
.
There are 7 periods
.
These signify the
number of electron
energy shells that
exist in an atom of an
element. Coinkydink! The maximum
number of shells an
atom can have is 7!
Period Number
Alkali Metals
YES!! For crying out loud,
it’s all significant!
How many electrons do
these have in the valence
shell?
Is this significant?
Having only 1 valence
electron means it is very,
very, very, very, very,
very…what?
REACTIVE!
Which of these is the
MOST reactive?
WHY?
How many valence
electrons do these have in
the valence shell?
Is this significant?
YES!!!
Having 2 valence electron
means it is still reactive. Just
less so than the Alkali
Metals.
Which of these is the
MOST reactive?
WHY?
WHY?
Alkaline Earth Metals
As you can see, these make up the
majority of the Periodic Table.
They are all solids except for
Mercury, which is liquid at room
temperature.
M
E
T
A
L
S
These metals mark the movement from
metallic to non-metallic elements. As you
move to the right, properties begin to lesson,
until you reach the metalloids.
Transition
Elements
(Metals)
Metalloids
The stair step of the Periodic Table.
These elements create the true boundary
line between metals and non-metals.
They contain only some properties of
metals, while sharing some of the
properties of non-metals.
Nonmetals
Well…they’re not metals.
Actually, a lot of them are gasses.
Ones a liquid.
Ok, Ok…These are the elements that make up the
composition of the atmosphere. This group also
contains the only other liquid that is listed on the
periodic table. Not to mention Carbon which is found
in all living things. That might be important.
Halogens
How many valence
electrons do these
have?
These are the non-metal
counterparts to Alkali Metals.
Is this relevant?
Of Course It Is!!!!
What does that mean?
To achieve a nice
stabilizing number of
valence e-, they only
need to gain 1 move e-.
Inert (Noble)
Gases
These are the Snobs of the Periodic Table.
Why?
They are not quick to
combine with any of the
other elements.
Why?
How many valence e- do they have?
Synthetics (Artificially Made)
What does this mean?
We make them through nuclear
fusion and neutron absorption.
These elements are thought to
have been present when Earth
formed, but have since decayed.
Review
1) What on the periodic table is equal to the sum of the particles in the
nucleus?
2) What is THE ID tag for each element?
3) What is atomic equilibrium? Why is this important?
4) How did Mendeleev first organize a periodic table?
5) Columns are called what two things? What does this tell us?
6) What are rows called? What does this tell us?
7) What equation do we use to find maximum electrons in a shell?
8) What are the most reactive metals? Non-metals? Why?
9) What are the least reactive elements called?
10) What are metalloids?
11) What are synthetic elements?
Bonus: How are synthetics made?
Radiation
Energy
transmitted in
the form of rays
or particles.
Can be helpful
and harmful.
Are you familiar with
this? Any experience
with it?
The Crookes tube was use to test the properties of
electricity across a void. Using a vacuum tube in which
cathode rays (electrons) were introduced, Crookes
demonstrated how those electrons would transmit from
one side of the tube to the other creating a connection.
He used thallium as a conductor. (Green glow)
Sir William Crookes
Alpha Particle
Cluster of particles
ejected from the nucleus
of radioactive material.
Consists of 2 protons and
2 neutrons.
Beta Particle
Gamma Ray
Electrons formed from
radioactive decay of an
element in which a
neutron converts to a
proton and an electron.
The most energetic photons of the
electromagnetic energy spectrum typically
released from the nucleus when beta particles
are created.
Well…what do they look like?
These are two or more atoms of the same or of different
elements that are chemically bonded together. These are
what create….
Things.
M
o
l
e
c
u
l
e
s
+
= Solution
+
Fe
+
Al
+
= Mixture
= Compound
Binary
Compounds
Chemical
compounds that
are composed
of only ______
elements.
Ionic Bond
Bond created between two elements,
where the valence electron from one
element is contributed to the other,
causing now positively and now
negatively charged particle to be
attracted to one another.
They share the valence electrons.
The cooperate. Co-valent.
Covalent
Bond
Polar Covalent
Bond
Bonds
Sharing of valence electrons
creates polar ends to the
molecule.
Nonpolar Covalent Bond
This is the process in which the
original substances go through a
transformation when they are
combined, resulting in a new
material being made. Reactions can
at time absorb energy, and at times
release energy.
Reaction
Does the new substance (product)
have to retain the properties of the
original?
Sodium
Chlorine
Stable
Ok…
There are several ways to
describe this:
1) A balance between proton
and electron numbers.
2) Inner electron shells are full.
3) 8 electrons present in the
outermost (valence) shell.
4) Non-radioactive.
Unstable
No Jokes Please.
1) Elements Decomposing on their own.
2) Highly or violently reactive elements such as alkali metals
and halogens.
3) Decaying with relatively short lifetime. Used of
subatomic particles.
4) Radioactive.
Nuclear Reaction
Fusion
Nuclei from atoms are
merged together to form
another element. In the
process energy is released.
Yes.. It is also a car. Not an
acceptable answer on any
work done for me in class.
Fission
Process in which a nuclei of a
dense atom is bombarded
with neutrons, causing a
division so two different
elements are created and
energy is released.
Review
1) What are the primary components of alpha particles?
2) What is the key particle associated with beta particles?
3) When solid is absorbed into a liquid, it is described as what?
4) When two substances are combined, yet their original properties
are still present, and they can be physically separated, it is what?
5) When two substances are combined creating a new substance, it
is called what?
6) All the bonds discussed create what building block of matter?
7) What are some ways to describe a material as being stable?
8) What is the difference between fusion and fission?
9) How could these two nuclear reactions be used beneficially?
Unit Review Outline
I. States of Matter
II. KMT and Thermal Dynamics
III. Elements and the Periodic Table
Paragraph Response Question