Unit 4 Lab: StoichiometryCHEM 1806
Purpose: To practice the concept of Stoichiometry
Materials: Student Supplied – Distilled water, paper towels, small paper cup, mug
LabPaq materials: 100 mL glass beaker, Funnel, 25 mL cylinder, Goggles, Digital Scale, Weighing boat, 2.5 g Calcium chloride, dehydrate, Filter paper, 2 g Sodium carbonate.
Procedure:
1. While wearing goggles, weigh out 1.0 g CaCl2 and put it into the 100 mL beaker. Record the actual mass of CaCl2 you are using in Table 1.
2. Add 25 mL of distilled water to the beaker and stir. This is now the “Calcium chloride solution”
3. Calculate how much sodium carbonate you will need for a full reaction. Write that calculation in the Results and Discussion section.
4. Weigh out the calculated amount of Na2CO3 and put it in a small paper cup. (Record actual mass in Data Table 1)
5. Add 25 mL distilled water to the paper cup and stir to make “sodium carbonate solution.”
6. Pour the sodium carbonate solution into the beaker with the calcium chloride solution.
7. Record observations. Write out the reaction of what occurred in the results section. (The solid is calcium carbonate.)
8. Fold the filter paper in half, then in quarters. Record the mass of the filter paper.
9. Place the filter paper in the funnel and open one side.
10. Place the funnel in a mug or other cup to balance it.
11. Carefully swirl and pour the contents of the beaker into the filter paper. (Don’t let the solution overflow.)
12. Rinse the beaker with 1-3mL of distilled water and pour that water into the filter paper as well. (If there is a little solid left in the beaker, leave it. It is experimental error.)
13. When the liquid has drained, lay the filter paper and precipitate on a plate or paper towels to allow it to dry. (mine took overnight, some people take 3 days)
14. When dry, weigh the precipitate + filter paper, record it, and calculate the mass of the precipitate.
15. In the discussion, calculate the theoretical yield and percent yield.
(4 pts) Data:
Table 1: Data
Mass of CaCl2
Mass of Na2CO3 needed
Actual mass of Na2CO3 used
Observation of reaction
Mass of filter paper
Mass of filter paper + precip
Actual yield of Calcium Carbonate
1. (3 pts) Calculate how much Na2CO3 you need to completely react your mass of CaCl2. (Show that calculation here)
2. (2 pts) Write out the reaction that occurred to form calcium carbonate. Remember to identify the phases and balance the equation.
3. (2 pts) Calculate the actual yield of Calcium Carbonate. (Show your work)
4. (2 pts) Calculate the theoretical yield of Calcium Carbonate. (Show your work)
5. (2 pts) Calculate your percent yield of Calcium Carbonate. (Show your work)
Insert a picture of your filter paper with yield for 2 pts extra credit. ;-)
When you are finished, save the file as LASTNAME_Stoich and upload it to the Dropbox for Unit 4 Labs.
Unit 4 Lab: Ionic ReactionCHEM 1806
Purpose: To observe several ionic reactions and practice net ionic equations
...
Unit 4 Lab StoichiometryCHEM 1806Purpose To practice the conce.docx
1. Unit 4 Lab: StoichiometryCHEM 1806
Purpose: To practice the concept of Stoichiometry
Materials: Student Supplied – Distilled water, paper towels,
small paper cup, mug
LabPaq materials: 100 mL glass beaker, Funnel, 25 mL
cylinder, Goggles, Digital Scale, Weighing boat, 2.5 g Calcium
chloride, dehydrate, Filter paper, 2 g Sodium carbonate.
Procedure:
1. While wearing goggles, weigh out 1.0 g CaCl2 and put it into
the 100 mL beaker. Record the actual mass of CaCl2 you are
using in Table 1.
2. Add 25 mL of distilled water to the beaker and stir. This is
now the “Calcium chloride solution”
3. Calculate how much sodium carbonate you will need for a
full reaction. Write that calculation in the Results and
Discussion section.
4. Weigh out the calculated amount of Na2CO3 and put it in a
small paper cup. (Record actual mass in Data Table 1)
5. Add 25 mL distilled water to the paper cup and stir to make
“sodium carbonate solution.”
6. Pour the sodium carbonate solution into the beaker with the
calcium chloride solution.
7. Record observations. Write out the reaction of what occurred
in the results section. (The solid is calcium carbonate.)
8. Fold the filter paper in half, then in quarters. Record the
mass of the filter paper.
9. Place the filter paper in the funnel and open one side.
10. Place the funnel in a mug or other cup to balance it.
11. Carefully swirl and pour the contents of the beaker into the
filter paper. (Don’t let the solution overflow.)
12. Rinse the beaker with 1-3mL of distilled water and pour that
water into the filter paper as well. (If there is a little solid left
in the beaker, leave it. It is experimental error.)
13. When the liquid has drained, lay the filter paper and
2. precipitate on a plate or paper towels to allow it to dry. (mine
took overnight, some people take 3 days)
14. When dry, weigh the precipitate + filter paper, record it, and
calculate the mass of the precipitate.
15. In the discussion, calculate the theoretical yield and percent
yield.
(4 pts) Data:
Table 1: Data
Mass of CaCl2
Mass of Na2CO3 needed
Actual mass of Na2CO3 used
Observation of reaction
Mass of filter paper
Mass of filter paper + precip
Actual yield of Calcium Carbonate
1. (3 pts) Calculate how much Na2CO3 you need to completely
react your mass of CaCl2. (Show that calculation here)
2. (2 pts) Write out the reaction that occurred to form calcium
carbonate. Remember to identify the phases and balance the
equation.
3. (2 pts) Calculate the actual yield of Calcium Carbonate.
(Show your work)
4. (2 pts) Calculate the theoretical yield of Calcium Carbonate.
(Show your work)
3. 5. (2 pts) Calculate your percent yield of Calcium Carbonate.
(Show your work)
Insert a picture of your filter paper with yield for 2 pts extra
credit. ;-)
When you are finished, save the file as LASTNAME_Stoich and
upload it to the Dropbox for Unit 4 Labs.
Unit 4 Lab: Ionic ReactionCHEM 1806
Purpose: To observe several ionic reactions and practice net
ionic equations
Materials: Student Supplied –distilled water
LabPaq materials: 24 well plate, 96 well plate, pipet (empty),
Ionic Reaction bag.
Procedure:
**The 24-well plate will hold the chemical droppers. The 96-
well plate is where the reactions will take place.
1. Load the well rows.
1. Place 2 drops of cobalt (II) nitrate solution into seven of the
A row wells.
2. Place 2 drops of copper (II) nitrate into seven of the B wells.
3. Place 2 drops of iron (III) nitrate into seven of the C wells.
4. Place 2 drops of barium nitrate into seven of the D wells.
5. Place 2 drops of nickel (II) nitrate into seven of the E wells.
When performing the following, NEVER TOUCH THE TIP OF
THE PIPET TO THE SOLUTION ALREADY IN THE WELL!
2. Load the well columns
6. Place 2 drops of sodium phosphate solution into five vertical
wells under column number 1.
7. Place 2 drops of sodium iodide solution into five vertical
wells under 2.
8. Place 2 drops of sodium sulfate solution into five vertical
wells under 3.
9. Place 2 drops of sodium chloride solution into five vertical
wells under 4.
4. 10. Place 2 drops of sodium bicarbonate solution into five
vertical wells under 5.
11. Place 2 drops of sodium carbonate solution into five vertical
wells under 6.
12. Place 2 drops of sodium hydroxide solution into five
vertical wells under 7.
3. Record all observations. If the solution is anything but
transparent, a solid has been formed. Milky = precipitate.
Data Table: (2 pts)
1
2
3
4
5
6
7
A
B
5. C
D
E
Results and Discussion:
Insert a picture of your well plate with the reaction mixtures. (5
pts)
Based on your observations, choose 10 wells that created a
precipitate and write the net ionic equations. (8 pts)
When you are finished, save the file as LASTNAME_Ionic and
6. upload it to the Dropbox for Unit 4 Labs.
Unit 3 Lab: VSEPRCHEM 1806
A. Natural Orientation of Volumes about a Central Point.
This part necessitates you have 6 balloons. Hold or tie them
together in the quantity identified in the table and describe the
shape in the table below.
Balloon Arrangement
Description of the Shape
Two-Balloon Set
Three-Balloon Set
Four-Balloon Set
Five-Balloon Set
Six-Balloon Set
B. Valence Shell Pairs: Single Bonds
7. Fill in the table below for the corresponding compounds. The
shapes and other information on pages 4-6 of this lab will be
helpful.
Molecular
Shape
Number of Bonds
About Central Atom
Shape
Description
BF3
BeCl2
CH4
PF5
SF6
8. C. Valence Shell Pairs: Single Bonds and Non-Bonding electron
pairs
Fill in the table below for the corresponding compounds. The
shapes and other information on pages 4-6 of this lab will be
helpful.
Molecular
Formula
Number of Bonds and
Non-Bonding Pairs
Shape
Desrciption
NF3
H2S
H3O+
PH3
ClO2-
9. D. Valence Shell Pairs: Single and Double Bonds and Non-
Bonding electron pairs
Fill in the table below for the corresponding compounds. The
shapes and other information on pages 4-6 of this lab will be
helpful.
Formula
Number of Bonds and
Non-Bonding Electron Pairs
Shape
Description
CO32-
SO2
H2CO
SO3
10. SO32-
NO2-
PO33-
When you are done, please save this file as
LASTNAME_VSEPR and upload it to the Unit 3 Lab DropBox.
Unit 2 Lab: ID Metal IonsCHEM 1806
Purpose: To identify metal ions by the colors they produce in a
flame. The colors and their energies are discussed in this unit.
11. The color is produced by electrons being promoted and then
relaxing to the ground state electronic structure. As the
electrons move, energy is released and their energy is displayed
as photons of light. Depending on the energy, a different color
is released. Red is low energy; violet (purple) is high energy.
Materials: Student Supplied – Lighter or matches; 8 paper-
stemmed cotton swabs (Q-tips) NOT plastic stemmed ones
LabPaq materials: Burner fuel, Goggles, 24-well plate,
Experiment bag “Identification of Metallic Ions”
Procedure:
1. Use the 24-well plate as a chemical holder, as shown to the
right.
2. Place about 0.5mL (20 drops) of sodium nitrate in the first
well of your well plate.
3. Place the chemical container in the well below the chemical
to keep track of which chemical is where.
4. Repeat with the remaining chemicals.
5. Light the burner.
6. Soak a cotton end in the first chemical.
7. Pass the soaked cotton through the flame until there is a
change in the flame color. (It might take 6 passes) Move the
cotton through fairly rapidly so the cotton doesn’t burn.
8. Record the color change in the data table below.
9. Repeat steps 6-8 with the remaining chemicals, including the
unknown.
10. All chemicals can be rinsed down the sink. Extinguish the
flame by carefully replacing the cap over the flame.
Data Table: (2pts)
Sodium Nitrate
Barium Nitrate
Calcium Nitrate
Cupric Nitrate
Lithium Nitrate
Potassium Nitrate
Strontium Nitrate
12. Unknown
Flame Color
Results and Discussion:
1. (8 pts) Is there a trend in the color of the flame and
corresponding placement on the periodic table? Discuss in terms
of energy levels and colors observed.
2. (5 pts) What is the identity of your unknown?
3. (5 pts) Insert a picture of your lab set up (try to get a picture
of the colored flame too – it isn’t easy!)
4. That’s it. Quick lab.
When you are finished, save the file as LASTNAME_Metals and
upload it to the Dropbox for Unit 2 Labs.