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Final Exam Review - Unit 4
Properties of Matter
1) A hot dog is cooked

Chemical or physical change?
Your reason:
2) Thousand Island dressing and mayonnaise are mixed to make “secret sauce” for hamburgers

Chemical or physical change?
Your reason:
3) Water is boiled in preparation for making pasta

Chemical or physical change?
Your reason:
4) A rock star gets a tattoo on his forehead

Chemical or physical change?
Your reason:
5) Explain the difference in the particles in each state of matter in regards to their energy, distance
from each other, and attraction to each other.
6) List two chemical and two physical properties that would distinguish water from motor oil.
7) Draw a phase change graph and label the different parts (solid heating, melting, liquid heating, etc)
8) Draw a triple point graph and label the triple point and critical point. Show where a solid, liquid and
gas exist on the graph. Make sure you label your axis.
9) Use the graph to answer the following questions:
a. What is happening at #2?
b. What number(s) represent where the liquid is being
warmed?
c. Which number(s) indicate potential energy increase?
d. What temperature is the boiling point of the substance?
e. What number(s) indicate where kinetic energy is changing?
10) Use the graph to answer the following questions:
a. Label the triple point and critical point on the graph.
b. You take a sample of CO2 at 0°C and 1 atm. WITHOUT
changing the temperature you increase the pressure to
73 atm. What phase change does the sample undergo?
UNIT 4 – KEY
1) A hot dog is cooked

Chemical or physical change? Cooking is generally thought of as being a chemical change.

Your reason: The properties of the hot dog (consistency, taste, etc) are different after cooking
than before, suggesting that drastic changes have been made.
2) Thousand Island dressing and mayonnaise are mixed to make “secret sauce” for hamburgers

Chemical or physical change? Physical change

Your reason: Mixing things doesn’t break or make chemical bonds
3) Water is boiled in preparation for making pasta

Chemical or physical change? Physical change

Your reason: The process of boiling doesn’t break the bonds in water molecules
4) A rock star gets a tattoo on his forehead

Chemical or physical change? Physical change

Your reason: The dye in tattooing ink doesn’t formally bond to the skin. - Reversible
5) Explain the difference in the particles in each state of matter in regards to their energy, distance from each
other, and attraction to each other. Gas – particles have high energy, move fast, far apart, low attraction.
Liquid – particles have medium energy, close together but moving, some attraction. Solid – low
energy, tightly packed, high attraction.
6) List two chemical and two physical properties that would distinguish water from motor oil. CHEMICAL – oil
is flammable, water and sodium react. Any reactions. PHYSICAL – color, smell, taste (ew!), thickness
7) Draw a phase change graph and label the different parts (solid heating, melting, liquid heating, etc)
See notes in your notebook (p 76)
8) Draw a triple point graph and label the triple point and critical point. Show where a solid, liquid and gas exist
on the graph. Make sure you label your axis. See notes in your notebook (p 78)
9) Use the graph to answer the following questions:
a. What is happening at #2? Solid is melting OR liquid is freezing
b. What number(s) represent where the liquid is being warmed? 3
c. Which number(s) indicate potential energy increase? 2, 4
d. What temperature is the boiling point of the substance? 100°C
e. What number(s) indicate where kinetic energy is changing? 1, 3, 5
10) Use the graph to answer the following questions:
a. Label the triple point and critical point on the graph. Check your notes to see if this is correct
b. You take a sample of CO2 at 0°C and 1 atm. WITHOUT changing the temperature you increase the
pressure to 73 atm. What phase change does the sample undergo? The sample CONDENSES as it goes
from a gas to a liquid.