Thurs 9-10 and Fri 9-11
Physical and Chemical Properties
Mrs. Wilson
Daily Quiz 1-7
•Make sure you are using the new daily
quiz form.
•Work by yourself. Work silently.
•Please follow the LASA honor code.
•Flip over your paper when you are
finished.
•Your purple sheets will be returned to you.
If you have questions, please hold them
until the lab.
Objectives: Phys/Chemical Changes
1. Distinguish between the properties of solids, liquids,
gases, and plasma.
2. Distinguish between physical and chemical changes and
properties, and use evidence to justify your claims.
HOMEWORK 1.7 Homework – Major Quiz Next Class
Agenda
1.
2.
3.
4.
5.
Warmup
Daily Quiz 1-7 /
A Note on Combining Operations + SF
Phases of State / Modeling Matter
Physical and Chemical Changes + Card
Sort
6. Start the Foul Water Lab
A Note on Combining Operations and Sig Figs
• When operations are combined together, follow the sig fig rule of the
operation you performed last to round your final answer. Examine
the values used in the previous (immediate) step to determine the
number of sig figs or decimal places to use for the final answer.
• Do not round intermediate operations – round only at the end, to
avoid systematic error.
Example: Density
A 45.67 g stone is placed in a graduated cylinder, and the liquid level
rises from 25.7 mL to 32.6 mL. Determine the stone's density.
Solve each problem, and round your final answer to the appropriate
number of sig figs.
1. (4.50
x 0.0375) – 0.0030 =
2. (15.037 + 3.92 + 0.00353) ÷ 0.0075 =
3. A silver sample weighing 65.309 g causes water
in a graduated cylinder to rise from 30.27 mL to
36.50 mL. Calculate the density of silver.
Solve each problem, and round your final answer to the appropriate
number of sig figs.
1. (4.50 x 0.0375) – 0.0030 = 0.16575 = 0.1658 (four decimal places)
2. (15.037 + 3.92 + 0.00353) ÷ 0.0075 = 2528.070… = 2.5 x 103
(You need two sig figs in your answer. 2500 is also OK.)
3. A silver sample weighing 65.309 g causes water in a graduated cylinder to rise
from 30.27 mL to 36.50 mL. Calculate the density of silver.
65.309 g / (36.50 – 30.27) mL
= 65.309 g / (6.23 mL)
= 10.48298…
= 10.5 g/mL (3 significant figures)
A change…
With a partner, discuss the
answers:
1. Describe the picture.
2. Is this change a
change of phase? If
so, what is the name
of the change?
3. Is this change a
physical change or a
chemical change?
Explain.
Classifying matter according to the changes it undergoes
If you can separate its parts by physical means - it’s a mixture, so you can… (for example)
• filter it
• distill it (boil off one or more of its components)
… but the components are the same. The properties of each component are identical.
ex. Salt water can be distilled to form salt and water (so salt water is a mixture)
If a chemical reaction is required to separate its parts - it is a compound.
• before the reaction, the properties of the matter will be the same throughout.
• after the reaction, different properties will be observed because you have formed
completely different substances due to the chemical change.
ex. Rust  Iron + Oxygen (so rust is a pure substance)
States of Matter PhET
• Observe the simulation carefully to determine the properties of solids, liquids,
and gases.
• We’ll look at each state in terms of:
1. Compressibility (do its particles let you compress it easily?)
2. Volume (definite – has a volume independent of the container? Or
indefinite?)
3. Shape (definite – has a shape independent of the container? Or indefinite?)
4. Average distance between particles
5. Molecular motion (fast? Slow? In place?)
6. Molecular arrangement (regular, flexible, none?)
A Diagram of a Plasma
A plasma is a gas, just at an extremely high temperature.
Phases of State pg. 23
With a partner near you, complete the
following quad Venn Diagram. (The
plasma circle may not have much.)
Properties to consider include:
Compressibility
Shape
Volume
Molecular Arrangement
Avg. Distance B/w Particles
Molecular Motion
(It is up to you to describe the properties accurately.)
gas
compressible
indefinite volume
v. large distance b/w particles
v. fast molecular motion
No arrangement
plasma
Compressible
Indefinite volume
Largest distance b/w particles
Fastest molecular motion
No arrangement
solid
indefinite
shape
definite shape
v. small distance b/w particles
v. slow molecular motion
regular arrangement
incompressible
def.
volume
larger distance b/w particles
faster molecular motion
flexible arrangement
liquid
States of matter
FYI: Plasma is
highly ionized
and temporary
and consists of
free electrons
and ions.
Modeling Matter – examples
Describe each sample of matter as
thoroughly as possible with regards to
state and classification. Explain your
choices.
1. Pure substance – only one type of atom
is present since only one color is used.
2. Element – each particle consists of only
one type of atom. Each particle is
diatomic.
3. Most likely a gas – large spaces exist
between each particle.
Modeling matter – examples
Describe each sample of matter as
thoroughly as possible. Explain your
choices.
Modeling matter (pg. 22)
• Think Pair Share: Classify each sample of matter, as
shown on pg. 22. Make sure to describe each
sample as thoroughly as you can.
• Some diagrams depict combinations – be careful!
Discuss this…
•Are phase changes – PHYSICAL CHANGES
or CHEMICAL CHANGES?
•How can you tell?
Physical changes
Think Pair Share:
Each of these
changes are physical
changes.
1.What are the
characteristics of
physical changes?
2.Give some
examples of
physical changes.
Physical changes
• Physical changes change the arrangement of the
particles, not chemical bonds.
• Physical changes change the appearance of the sample.
• Physical changes include changes of state, dissolving,
and changing appearance.
Chemical changes
Think Pair Share:
Chemical changes involve the breaking of chemical bonds and
the formation of new particles and new chemical bonds.
Describe a possible arrangement that shows a chemical
change.
Chemical changes
• Chemical changes break and form chemical bonds.
• Chemical changes are signaled by changes in odor,
dramatic changes in color, the formation of a new gas,
or the formation of a new solid compound
(precipitate).
• Chemical changes involve the formation of new
substances (that were NOT present before the change)
Physical and Chemical Properties
(See pg. 6)
• All the properties listed on Pg. 6 are physical properties.
• The ability to undergo change of phase is a physical property.
• Solubility (ability to dissolve in a solvent) is a physical property.
• pH is a physical property.
• Intensive physical properties can be used to identify a substance – extensive
properties cannot.
Chemical properties involve chemical changes and include:
• The ability to decompose (or not to)
• The ability to rust or tarnish (or not to)
• The ability to combust (or not to)
• The ability to react with another chemical (or not to)
Physical and Chemical Properties card sort
• Get a set of cards from the Out In. You can work with
one partner.
• Together, you’ll sort the cards into four piles, spread
out over your desk: Intensive Physical Properties,
Extensive Physical Properties, and Chemical
Properties.
• Have your layout checked.
Foul Water Lab
•
•
•
•
•
•
•
•
•
•
•
•
Find “1.8 Investigation: Foul Water” in the back of your packet.
Record everything on the Foul Water lab sheet.
Read the Introduction and the procedure carefully.
Get LESS than 100 mL of the foul water for your initial sample. Your graduated
cylinder can’t measure past 100 mL, so it’s useless to get more.
The flask is very oily – be careful!
Label a beaker with your names and class period with a black Sharpie.
You will use a square of Parafilm to cover the top of it to store for next time.
Please put trash into the bins, not the sink.
Please refrain from eating or drinking anything.
Do not pour anything out into the sink.
Make sure to read ALL volumes with one uncertain digit and a unit.
Disposal of oil goes into the large beaker up at the front.
Goggles are needed, but aprons are not.
Exit Ticket
What did you learn today about physical and chemical
properties, changes, and the states of matter?
End of Class Procedure: Complete and turn in your exit ticket
by yourself. You may not use any notes. Put your books etc.
away. Wait for dismissal. Please, no phones! Clean up your
table. When you are dismissed by me (not the bell), push in
your chairs straight as you leave.
Homework: 1.7 Homework. Major Quiz next class!