Finding the Mole

With Lab Partners: Eri M. and Melanie F. 

Purpose: 

To observe reactions that form solids and to take note of the amount of product formed by different ratios of reactants.  

Procedure:

Part I

• Firstly, label 5 test tubes with tape numbering them 1 through 5

• Regard the table  below and add appropriate amounts of .10 M CaCl2 (aq) Calcium chloride and .10 M Na2CO3 (aq) Sodium carbonate. 

• Swirl the test tube to mix reactants. Set the test tubes on the test rack and allow for the solid forming to sink to the bottom of the tube (about 10 minutes). While the solids are settling, start on Part II of the experiment. 

• Finish the experiment after the solids have settled by measuring and recording the height of the solid in the test tube, 

•   Table of amounts for each test tube + height:

• Test Tube                             1             2           3            4            5

• mL of CaCl2                         4             6          12           18          20

• mL of Na2CO3                     20           18         12           6             4

• Ratio: CaCl2 to Na2CO3=   1:5          1:3         1:1         3:1         5:1

Post-swirl






Part II 

• Label 5 test tubes 6 through 10  

• Regard the table  below and add appropriate amounts of . 10 M CuSO4 (aq) Copper (II) Sulfate and .10 M NaOH (aq) Sodium Hydroxide. 

• Swirl the test tube to mix reactants. Set the test tubes on the test rack and allow for the solid forming to sink to the bottom of the tube (about 10 minutes). While the solids are settling, start on Part II of the experiment.

• Finish the experiment once the solid has settled at the bottom of the test tube by measuring and recording the height of the solid in the test tube. 

•  Table of amounts for each test tube + height:

• Test Tube                               6               7           8                 9              10

• mL of CuSO4                          4               8          12               16            20

• mL of NaOH                           20             16         12                8              4

• Ratio: CuSO4 to NaOH=         1:4            1:2        1:1              2:1           4:1

The settled solid in the test tubes at the end of Part II

Background
CaCl2 (aq) + Na2CO3 (aq) ->  CaCO3(aq) + 2NaCl2(s)
CuSO4 + 2NaOH -> Na2SO4 (s) + Cu(OH)2 (aq)
By limiting reactants and using ratios of each reactant, the amount of solid produced  is also limited.

Materials

• 12 x 75 mm test tubes (10)

• Test tube rack

• Marker and tape to label test tubes

• Pipette

• 60 mL of .10 M CaCl2 (aq) Calcium Chloride

• 60 mL of .10 M Na2CO3 (aq) Sodium Carbonate 

• 60 mL  of .10 M CuSO4 (aq) Copper (II) sulfate

• 60 mL of .10 M NaOH (aq)  Sodium Hydroxide 

Safety
CaCl2 (aq), irratant to skin, eyes, and if ingested or inhaled. Can permeate skin and harmful (Scienelab.com Clacium chloride). 
Na2CO3 (aq) Hazardous, irritant to skin and eyes. Poisonous if swallowed (Scholar chemistry) 
CuSO4(aq) Irratant to skin, eyes and respiratory system. Hazardous if ingested/inhaled. (TMC)
NaOH (aq) Irratant, corrosive and permeator to skin. Harmful if ingested/inhaled. Corrosive, irritant to eyes (Sciencelab.com Sodium Hydroxide). 


Hypothesis
Based upon the equation for part I: CaCl2 (aq) + Na2CO3 (aq) ->  CaCO3(aq) + 2NaCl2(s) , the most solid will be produced when CaCl2 and Na2CO3 are at a ratio of 4:1 in the test tube.  For Part II, the most solid wil appear in the tube with a ratio of 1:4 for CuSO4 to 2NaOH. 

Data
Part I
Test Tube:                    1                   2               3                 4                  5
Height of solid              0.2               0.4             0.3              1.1              1.0 
(in Centimeters)
Part II
Test Tube:                     6                  7                 8                 9                  10
Height of solid                1.1               0.9              0.7             0.3               0.2  
(In Centimeters)


Calculations/ Analysis
In this lab, for part I, the ratio that produced the largest amount of solid was the 4:1 ratio of CaCl2 to Na2CO3
For part II, the ratio with the greatest amount of solid was the 1:4 ratio of CuSO4 to NaOH
The hypothesis is supported because in the experiment for both part I and II showed that higher amounts of solid were produced at the predicted ratios (4:1 for part I and 1:4 for part II)

Graphs

Conclusion

The Hypothesis was supported in that the most solid appeared in the tube containing a 4:1 ratio in part I and a 1:4 ratio in part II  

Discussion of Error

Error in this lab could be due to that in the act of swirling the test tube, some of the matter in the test tube was lost. 






Citations
Sciencelab.com. Chemicals and laboratory equipment. (5/21/2013). Material Safety Data Sheet: Calcium chloride anhydrous MSDS. http://www.sciencelab.com/msds.php?msdsId=9923251
Scienelab.com Chemicals and laboratory equipment (5/21/2013). Material safety data sheet: Sodium hydroxide. http://www.sciencelab.com/msds.php?msdsId=9924997
Scholar Chemistry (9/22/2012). Material Safety data sheet.  http://www.scholarchemistry.com/msds/Sodium_Carbonate_Solution_1.0M_648.10.pdf
TMC. Material data safety sheet. (Feb.13. 2003).  http://tmc.co.kr/home/link/Microsoft%20Word%20-%201-2-2-2-15MSDS%20_copper%20sulfate%20Pentahydrate_.pdf

 

Concentrate on Chemistry!

With lab partner Fabiana B.

Purpose: To learn from solutions and look closer at dissolved substances in solutions.

Hypothesis: Predictions: 9 tablespoons of sugar and 9 tablespoons of salt.

Materials:

• Sugar, C12H22O11 (60 g)
• Salt, NaCl       (60 g)
• Water, H2O (200 mL)
• 250 mL beakers (2)
• Balance
• Stirring Rod
• 2 spatulas or plastic spoons
• 2 green or red gummy bears.

Safety:

Sugar can be slightly hazardous after prolonged exposure to skin, eyes, and if inhaled.

(Material Safety Data Sheet, Sugar)

Salt can be irritant to skin, eyes, and if inhaled.  
(Material Safety Data Sheet, NaCl)

Procedure:

1. Firstly, make a prediction about how much (in grams) sugar can be dissolved in 100 mL of water. Do the same for the salt.
2. Find the combined mass of a beaker with 100 mL of water in it.
3. Then, add sugar to the water until the water will no longer dissolve any more sugar. Enter data into the table about how much sugar it took to saturate the water.
4. Repeat the steps using fresh water and table salt.

Part II

1. Put a gummy bear into the sugar solution overnight and record observations.

Background:

This lab studies the point at which water is saturated with sugar/ salt. Saturation occurs when the solute (in this lab, water) can dissolve no more solvent (in this case, sugar or salt). Concentration is how much solute there is per a solution.

Data:

_________________________________________________________________________________

Solid Solute Volume of Mass of Mass of Volume of

water (mL) water and solution and solution (mL)

beaker (g) beaker (g)

_________________________________________________________________________________

Sugar 100 113.08 221 165

C12H22O11

_________________________________________________________________________________

Salt  100 113.23 133.1 100

NaCl

_________________________________________________________________________________

Calculations

1)To find mass of solid added:

Mass of solution and beaker - Mass or water and beaker= Mass of solid added

Sugar: 221.0-113.08= 107.92

Salt: 133.1-113.23= 19.87

2) To find mass of solid per liter of solution:

Mass of solid added/ (volume of solution (mL)/ 1000, to convert to liters)

107.92/(165/1000)= 654.06 g/L

3) To find moles of solid added (mol)

(Mass of solid added) (1 mol)/ (mohler mass)= Moles of solid added

107.92/ 342.11= .315 moles

4) To find the Moles of dissolved solid/ liter:

Moles of solid added/ volume of solution (L)

.315/ .165= 1.90 moles/Liter

_________________________________________________________________________________

Mass of                        Mass of                             Moles of                          Moles of

solid added dissolved solid solid added dissolved solid

(g) per liter of solution (mol) per liter of solution

(g/L) (mol/L)

_________________________________________________________________________________

Sugar: 107.92               654.06                              .315                                     1.90

________________________________________________________________________________

Salt:    19.87                 198.7                                .339                                     3.39         

________________________________________________________________________________

Part II:

1) The bears in the solution and their reaction to the solutions in which they are placed in vary.

A) This bear was in water, and expanded greatly and held more water than any other solution. This is because in an unsaturated solution, the water is trying to absorb more and is moving throughout the gummy bear to expand it.

B) This is a mostly water solution, however, with some sugar and this has an impact on the size of the gummy bear, the more saturated the sugar solution becomes, the less the water will expand the gummy bear because there is less water to run through the gummy bear. 

C) This is a further degree of letter B in that there is more sugar in the C solution than there is in either A or B and this prevents the gummy bear's expansion. This gummy bear is smaller than either A or B because of the higher concentration of sugar. 

D) This is a more though not completely saturated solution. The gummy bear is even more compressed than either A, B, or C and this is due to the high sugar content of the water. 

E) This gummy bear has hardly expanded at all and this is to due, as already outlined, to saturation. The solution in which the gummy bear is in is a corn syrup solution. It cannot hold any more sugar. and there isn't enough water to move through the gummy bear and expand it.

2) If it was sugar moving into and through the bears, the sugar solution would be the most inflated and the water solution would have the most compressed gummy bears. 

3) The gummy bear left overnight shrunk, like letter E solution. This shows that the solution is saturated because the gummy bear was not only heavier than the solution and sunk, it also didn't expand in size. 

Discussion of Error: In this lab, there was an error in which part of the salt solution was spilled before the volume could be measured for the second time. Thus, the reason for only 100 mL being recorded for the volume of the salt solution.

Conclusion: The original hypothesis was wrong because the water was able to hold 20 teaspoons of sugar and the salt water saturated at 12 teaspoons. The purpose was carried out in that saturation and the process of saturating was witnessed.

Questions:

1) Because the NaCl Molecule is a lot smaller than a sugar molecule, a lot more mols of NaCl were able to fit into one liter. With the dissolved solid/ liter, the number is much greater because the sugar solution was able to hold and dissolve more than the salt solution could dissolve of salt.

2) The volume is different because in the lab, matter was added to the water, it is no longer just a water solution but a water and sugar/ salt solution. This extra sugar/ salt takes up more space than the water did alone.

3) 12 percent of 2.3 (g) =.27 
.27/ .001= 270
(.27)/ (342.119)
.000789/ .001
The gummy bears contain a concentration of .789 mols of sugar per liter.

Citations:

Material Safety Data Sheet. Sucrose. thesciencelab.com. Retrieved from:

http://www.sciencelab.com/msds.php?msdsId=9927285.

Material Safety Data Sheet. Table Salt, NaCl. thesciencelab.com. Retrieved from: http://www.sciencelab.com/msds.php?msdsId=9927593

Carolina Wasinger
Ms. Bowser
Chemistry
3/6/2016

Can I have change for that?

Purpose: To look and study examples of physical and chemical changes and how these changes relate to the mass of the reactants and products. 

Hypothesis: 

1. Equation: NaCl (s) ->NaCl (aq)  

                         Hypothesis: The mass  will be the same before and after combining (because of conservation of mass) the H2O and NaCl (s) to form NaCl (aq)  

    

     2. Equation: Na2CO3 (aq) + CaCl2 (aq)  ->  2NaCl(aq) + CaCO3 (s)

                          Hypothesis: The mass of the products and reactants in this experiment will be the same (due to the law of conservation of mass)

   3. Equation:  Na2CO3 (aq) + 2C2H4O (aq) -> 2NaC2H3O2 (aq) +  H2O (l) +  CO2 (g)

                         Hypothesis: The mass in this experiment will decrease after the reactants are combined; because a gas will form (CO2 (g)) which will escape the beaker therefore decreasing the total mass of the combined products. 

Procedure: 

For each of the three equations, weigh the mass of the reactants before and after combining. Measure reactants as instructed for each of the equations. Be sure to measure both masses with both containers on the scale. 

                                                                                         (Martyn F. Chillmaid)

Equation 1:  1 gram of  NaCl (s) and 20 mL of water (H2O) in separate containers. 

Equation 2:  20 mL of  Na2CO3 (aq) and 20 mL CaCl2 (aq)  in separate containers.  

Equation 3:  20 mL of  Na2CO3 (aq) and 20 mL of  C2H4O2 (aq) in separate containers. 

Safety: 

NaCl irratent to eye, skin and if ingested or inhaled (Material Safety Data Sheet: Sodium Chloride MSDS)

H2O, Non-corrosive, non-irratant, non permeator for skin. (Material Safety Data Sheet. Water MSDS.)

Na2CO3 (aq), irratint to eyes and skin. Can cause lung irritation and blindness. severity of skin corrosion depends upon length of time substance on skin. ( Material Safety Data Sheet: Sodium carbonate monohydrate MSDS) 

 CaCl2 (aq), irratant to skin, eyes, and if ingested or inhaled. Can permeate skin and harmful ( Material Safety Data Sheet: Calcium chloride anhydrous MSDS). 

 C2H4O2 (aq), irratint to skin, eyes and if ingested or inhaled. Permeates skin (Material Safety Data Sheet: Methyl Formate MSDS)

Materials: 

• Balance
• Transparent plastic cups
• water
• NaCl (s), 1 g
• 1.0 M Na2CO3 (aq) 40 mL
• 1.0 M CaCl2 (aq)
• Acetic Acid, C2H4O2, 20 mL
• Graduated Cylinder

Background

The Law of Conservation of Mass states that matter can be changed from one form to another without the mass of the matter fluctuating. At the micro level, this means that no single atoms are gained or lost (excluding error) during the experiment. For the macro level, we can weigh the amount of mass in matter before and after the experiment to prove this law (The Law of Conservation of Mass.)

Data:

Reaction #1

Reactants/Products:   Chemical Name                Description                  Mass before      Mass after

____________________________________________________________________________

NaCl(S)                  Sodium Chloride                             Light colored powder      23.45

H2O                        Water                                               Clear liquid             

____________________________________________________________________________           

NaCl (aq)              Sodium Chloride (aq)                     Cloudy in the water                                  23.425

____________________________________________________________________________

Reaction #2

Reactants/Products:   Chemical Name                Description                         Mass before      Mass after

_________________________________________________________________________________

Na2CO3(aq)            Sodium Carbonate (aq)            Watery substance          45.70 

CaCl2 (aq)               Calcium Chloride                      Watery and pale _________________________________________________________________________________

CaCO3 (s)              Calcium Carbonate                     Powder in cloudy water                       45.673

NaCl (aq)               Sodium Carbonate                      Watery 

Reaction #3 

Reactants/Products:   Chemical Name                Description                         Mass before      Mass after

_________________________________________________________________________________

Na2CO3 (aq)          Sodium Carbonate               Thin/ watery                       41.7

C2H4O2 (ag)         Vinegar                                 Clear, liquid 

_________________________________________________________________________________

NaC2H3O2 (aq)     Sodium Carbonate                Clear liquid                                                   40.1

CO2 (g)                   Carbon dioxide                    Clear gas                              

_________________________________________________________________________________  

Calculations:

In reaction #3)    41.7- 40.1= 1.6

1.6 mL of gas escaped during the 3rd experiment. 

Percent Error

Reaction # 1      =  .09 %

Reaction #2       =  .044%

Reaction #3       =   3.84%

Discussion of Error

The error in this lab was due to the swishing method in which the products were combined using a method of swishing the tubes to insure proper combination of the compounds. This method perhaps led to stray drops falling from the test tube; thus, a decrease in the compounds overall mass. In experiment #3, the reason for such a large percent error was really not an error; rather, the gas that was formed in the container during the reaction escaped the container thus decreasing the overall final mass. 

Questions:

5) SO3 (g) + H2O (l) -> H2SO4 (aq)

H2SO4 could be ingested or absorbed through the skin. 

6) 2Li + 2HCl -> H2 + 2LiCL (aq) + H2 (g)

2LiCl could be absorbed through the skin or be ingested. H2 could be inhaled. 

7) AgNO3 (aq) + NaOH (aq) -> NaNO3 (aq) + AgOH (aq) 

Could be ingested or absorbed through the skin. 

Conclusion:

The hypothesis of this lab was correct in all the predictions of the masses of the three reactions before and after the experiment. The purpose of this lab was fulfilled in that the class studied physical and chemical changes and related these changes to mass.

Citations:

Martyn F. Chillmaid. Science Photo Library. http://www.sciencephoto.com/media/4621/view

Sciencelab.com. Chemicals and laboratory equipment. (5/21/2013). Material Safety Data Sheet: Sodium Chloride MSDS. Retrieved from:  http://www.sciencelab.com/msds.php?msdsId=9927593

Sciencelab.com. Chemicals and laboratory equipment. (5/21/2013). Material Safety Data Sheet: Water MSDS. Retrieved from http://www.sciencelab.com/msds.php?msdsId=9927321

Sciencelab.com. Chemicals and laboratory equipment. (5/21/2013). Material Safety Data Sheet: Sodium carbonate monohydrate MSDS. Retrieved from: http://www.sciencelab.com/msds.php?msdsId=9927591

Sciencelab.com. Chemicals and laboratory equipment. (5/21/2013). Material Safety Data Sheet: Calcium chloride anhydrous MSDS. http://www.sciencelab.com/msds.php?msdsId=9923251

Sciencelab.com. Chemicals and laboratory equipment. (5/21/2013). Material Safety Data Sheet: Methyl Formate MSDS.  http://www.sciencelab.com/msds.php?msdsId=9926061

The Law of Conservation of Mass. http://www.chem.wisc.edu/deptfiles/genchem/sstutorial/Text1/Tx14/tx14.html

Carolina Wasinger
Ms. Bowser
Chemistry
January 24, 2016

I am in high school, I don't have any degrees

Purpose: To use a thermometer, learn how it works, and observe how changes in temperature effect the thermometer. 

Materials: 

Part I: 

• Small glass vial
• (3) 250 mL beakers
• Hot plate
• Ice 
• Ice water
• Salt
• Small metric ruler
• Ethylene glycol (antifreeze) (25 mL in each thermometer
• Rubber Septum or rubber stopper
• Plastic straw
• test tube holder, wire
• Permanent marker

Part II:

• 250 mL beakers (3)
• Ice
• Test tube holder, wire
• Hot plate
• 10 mL graduated cylinder

Safety: 

Hot Plate: Be sure when using the hot plate (to boil water) to not directly touch the heated surface of the hot plate as burns may result. 

Ethylene Glycol (Antifreeze)( HOCH2CH2OH): Being exposed to this substance for large amounts of time can result in death. Can be harmful/ irritating to skin and eyes and permeate. Hazardous for inhalation (Material Safety Data Sheet). 

Background: 

The Thermometer is used to measure temperature and there two commonly used units of measurement: Celsius and Fahrenheit. Celsius units were invited by  Anders Celsius, an astronomer (The Physics Classroom). On the Celsius scale, Water boils at 100 degrees and freezes at 0 degrees. Physicist Daniel Fahrenheit invented the other commonly used unit of measurement for temperature, degrees Fahrenheit (The Physics Classroom). In degrees Fahrenheit, water freezes at 32 degrees and boils at 212 degrees.

For creating a scale for a thermometer, pick a number for a certain temperature (i.e. 6 degrees for water freezing and 103 degrees for water boiling).

Typically, a thermometer consists of a liquid inside of a clear tube. As temperatures rise, so does the liquid inside the thermometer and when the temperature falls, the height of the liquid inside the tube falls as well (Mary Bellis). This occurs because when higher temperatures occur, the molecules become farther apart and the only way to create more room for the molecules to move about is by increasing volume and to do that, the liquid must expand upwards (How Things Work). When the temperature falls, the molecules come closer together (How Things Work). 

Questions from 3.4

1. The rising and falling of the Ethylene glycol in the tube. 
2. The temperature change. The density is changing and the volume . The higher temperatures forces the liquid in the tube to expand and travel upwards in the tube.

     3.   A)For boiling water, 212 degrees Fahrenheit is equal to 237.44 degrees Wasinger. For ice water, 32 degrees Fahrenheit is equal to 35.84 Wasinger. I chose these numbers because I wanted an even more exact measurement of temperature than Fahrenheit, so even smaller degrees.

           B) The room temperature is 82.8 degrees Wasinger or 69 degrees Fahrenheit. To convert Fahrenheit to Wasinger: Multiply the degrees in Fahrenheit by 1.2.

Procedure:

Part I:

• Put the thermometer in the varying heat conditions (there are five total heat tests for the thermometer) and record where the thermometers' liquid stops climbing by marking it with a permanent marker. 
• Measure the temperature with the thermometer at room temperature, when it is placed in a hand (body temperature), when it is placed in boiling water, when it is placed in ice water, and when it is placed in a mixture of ice water and salt. 

Part II:

• Fill a 250 mL beaker with 200 mL of water. The water should be heated to 80 Degrees Celsius. In another 250 mL beaker, put in room temperature water. Put ice into the last beaker. 
• Use the test tube clamp to place the 10 mL graduated cylinder into the hot water beaker with the opening of the test tube almost touching the bottom of the beaker. Record what you observe. 
• Remove the 10 mL graduated cylinder from the hot water and place it into the room temperature water following the same method as used with the hot water. Record observations.
• Add the ice from the third beaker into the room temperature water using the same method used for the previous two beakers. Write down any observations.

Analysis:

• Changes were observed during the lab due entirely to the change in temperature at each of the individual stations in part I. In part II, the changes were due to the varying temperatures of the water tested. 

Discussion of error, In this lab, there was no error between the conversions from Degrees Wasinger to Fahreinheit, Celsius and Kelvins. 

Conclusion: 

In conclusion, the results for this lab are as follows:

Part I:

Condition                                                            Centimeters                               Degrees Wasinger

Salt Ice Water(general chemistry online)            7.5                                              12                

Ice Water                                                              9                                                 36

Room Temp                                                         11.9                                            83

Body Temp                                                          14                                               117.3

Boiling Temp                                                       32                                               237

Part II:

Hot Beaker: Condensation, steam bubbles

Room Temperature beaker:  Nothing occurred

Iced beaker: Bubble inside graduated cylinder

• The temperature for the conditions tested were as to be expected. However, part II of the lab had differently anticipated results. A huge bubble formed inside the graduated cylinder in the last test with the ice water. 

Questions: 

Citations: 

General Chemistry Online. Why isn't the lowest possible temperature for salt/ice/water mixture 0?. (n.d). Retrieved from: http://antoine.frostburg.edu/chem/senese/101/solutions/faq/zero-fahrenheit.shtml

How Things Work. How does the thermometer work. (n.d.). Retrieved from:http://www.energyquest.ca.gov/how_it_works/thermometer.html

Mary Bellis. The history of the thermometer. Retrieved from: http://dwb4.unl.edu/chem/chem869m/chem869mlinks/inventors.about.com/science/inventors/library/inventors/blthermometer.htm

Material Safety Data Sheet. Ethylene glycol MSDS. In: Sciencelabchemicals.com. Chemicals and laboratory equipment. Retrieved from: http://www.sciencelab.com/msds.php?msdsId=9927167

Purdue Owl. Joshua M. Paiz, Elizabeth Angeli, Jodi Wagner, Elena Lawrick, Kristen Moore, Michael Anderson, Lars Soderlund, Allen Brizee, Russell Keck.  2015-03-27 01:19:35. Retrieved from: https://owl.english.purdue.edu/owl/resource/560/10/

The Physics Classroom. Temperatures and Thermometers. (n.d.) Retrieved from:http://www.physicsclassroom.com/class/thermalP/Lesson-1/Temperature-and-Thermometers