Transcript Chem Catalyst

Chem Catalyst
• Consider water, a penny, and oil. Which has the
highest concentration of stuff? Which has the
lowest? How do you know?
• If you had all three objects in a cup, draw a picture of
where they would be, label the objects, and use dots
to show the concentration of stuff in each object.
• If you are randomly chosen, please draw your picture
on the board.
Check-In
• You have 3 cm3 of substance B, which
has a density of 3 g/cm3. How many
grams of B are there? Draw a picture to
justify your answer.
Chem Catalyst – 9/22
Yesterday we found that the mass of the 10
cm silver rod was 35.6 grams. We also
found that the volume was 13 ml.
Additionally, we found that the mass of the
5 cm gold rod was 55.4 grams while the
volume was 7 ml.
Which has a greater “concentration of stuff”
– the 10cm silver rod or 5cm gold rod?
How do you know?
Chem Catalyst – 9/23
Write down as many ways as you can to
describe the density of the picture above.
Each box represents 1 cm3 and each dot
represents 1 gram.
Check-In
• You have a sample of copper with a
mass of 36 grams. The density of
copper is 9.0 g/cm3. How many cm3 of
copper do you have? Draw a picture to
help explain your answer.
Chem Catalyst – 9/24
Aluminum has a density of 3
g/cm3. If you have 27 grams of
aluminum, what is the volume?
Draw a picture to explain your
answer.
Practice Problems
Copper has a density of 7.0 g/cm3. If you
had 49 g of copper, how many cm3 of
copper would you have?
Show all your work, making sure to
include units!
Practice Problems
Titanium has a density of 5 g/cm3. How
many grams of titanium would you have
if you have a volume of 9 cm3?
Show all your work, making sure to
include units!
Practice Problems
During chemistry lab, you find a chunk of
unknown metallic substance. You
measure the mass and found out it is
67.23g. Using water displacement, you
find its volume to be 3.48ml. What is
the density of the unknown substance?
Show all your work, making sure to
include units!
Chem Catalyst
• In 1999, the United States Mint produced a
coin called the Golden Dollar. It features
an image of Sacagawea, the famous
Native American guide for Lewis and
Clark. It has a mass of 9.8 g and a volume
of 1.1 ml.
• Is this coin truly gold? Explain.
Notes
• Density is a property that does NOT
change with the size, shape, or amount
of substance you have.
Notes
• Density can be used to identify what
something is made of.
Material
Density (g/cm3)
Aluminum
2.7
Tin
7.3
Titanium
4.5
Platinum
21.3
110
100
90
80
Mass (g)
70
60
50
40
30
20
10
0
0
10
20
30
40
50
60
70
Volume (mL)
80
90 100 110
Check-In
• You measure out 32 ml of liquid in a
graduated cylinder. You drop in a metal
cylinder and watch the water level rise
to 58 ml. What is the volume of the
metal cylinder?
• The mass of the metal cylinder is 38 g.
What is it’s density?
Chem Catalyst
• There are two bottles on a shelf in a
chemistry lab. Both contain a shiny
metal substance that resembles gold.
Bottle A is labeled Au (s). Bottle B is
labeled FeS2 (s).
– Do you think both bottles contain gold?
Why or why not?
– What do you think the symbol on the
bottles mean?
Check-In
Imagine you find a vial labeled
Na2SO4(aq). What does the
label tell you about what is in
this flask?
ChemCatalyst – 9/30
• You have 20cm3 of titanium. How many
grams of titanium do you have?
• You have 70 grams of tin. How many
cm3 of tin do you have?
Material
Density (g/cm3)
Aluminum
2.7
Tin
7.3
Titanium
4.5
Platinum
21.3
Chem Catalyst
• You find a piece of metal ON THE ground and
want to identify it. You take a graduated
cylinder and fill it up to 25 mL. When you put
the metal in, the water rises to 30 mL. When
you place the metal on the scale, it weighs
22.5 g. What is the density? What type of
metal is it?
Material
Density (g/cm3)
Aluminum
2.7
Tin
7.3
Titanium
4.5
Platinum
21.3
Test Review
1.) What is the volume of
the liquid shown on the
right?
Answer: 36.5 mL
Test Review
2.) What is this piece of lab
equipment called?
Answer: Erlenmeyer flask
Test Review
3.) What piece of lab
equipment would you use
to most accurately
measure the volume of a
liquid?
Answer: graduated
cylinder
Test Review
4.) Which of the following is NOT
matter?
Air
Energy
Helium
Answer: energy
Sand
Test Review
5.) What is this piece of lab
equipment called?
Answer: beaker
Test Review
6.) Which of the following IS considered
matter?
Heat
Wind
Clouds Sound
Answer: Clouds
Test Review
7.) True or False
Matter can always been seen.
Answer: False, sometimes matter cannot
be seen
Test Review
8.) If something is considered matter, it
must have both _______ and ________
Answer: Mass and Volume
Test Review
9.) True or False
You should always put your bookbag or
purse on the lab table.
Answer: False
Test Review
10.) What type of lab equipment would you
use to measure the mass of something?
Answer: electronic scale or balance
Test Review
11.) Imagine that you take a graduated
cylinder and place 20 mL of water into it.
Then, you place a metal cylinder into the
water and the water rises to 42 mL.
What is the volume of the metal cylinder?
Answer: 22 mL
Test Review
12.) The mass of an empty graduated
cylinder is 24.3g. You pour 30ml of water
into the cylinder, measure the mass again,
and find that it is now 56.2g. What is the
mass of the liquid?
Answer: 31.9 g
Test Review
13.) Neodymium has a density of 7.0 g/cm3.
Draw a picture of 5 cm3 of neodymium.
Test Review
14.) Sulfur has a density of 2.0 g/cm3. Draw
a picture of 16 g of sulfur.
Test Review
15.) Copper has a density of 9.0 g/cm3.
Draw a picture of 3 cm3 of copper.
Test Review
16.) What is the difference between an
observation and an inference?
Answer: Observation = 5 senses
Inference = what you THINK is
happening
Test Review
17.) What is the density of a glass marble
that has a mass of 18.5 g and a volume of
6.45 cm3? Write the density ratio AND
reduced density ratio.
Answer: 2.86 g/cm3
Test Review
18.) What is the density of a piece of metal
that has a volume of 30.0 ml and a mass
of 252 g? Write the density ratio AND
reduced density ratio
Answer: 8.4 g/ml
Test Review
19.) What units are used to measure the
volume of a substance? (We have used 2
in class)
Answer: mL and cm3
Test Review
20.) Mass of plastic object = 4.3 g
Volume of plastic object = 3.8 ml
Density of Liquid A = 1.0 g/ml
Density of Liquid B = 1.18 g/ml
Will the plastic object float, sink or
subsurface float in liquids A and B?
Answer: Sink in Liq A, Float in Liq B