All Labs

Study Guide

Labs & Post Labs

Reaction in a Bag Lab

I. Purpose: to record the observations that occur when multiple chemicals are combined and to use or observations to understand the reaction of the chemicals.

II. Procedure:

1. Observe and record of solid A and B in data table.

2. Waft red liquid and record odor in data table.

3. Lay open plastic bag on table.

4. Put 1 spoonful of solid A in corner of the bag.

5. Put ½ spoonful of solid B into the other corner of the plastic bag.

6. Keeping bag flat, pour 5mL of red liquid into the bag.

7. Seal bag tight and mix substances.

8. Observe and touch bag

III. Materials:

1. Substance A and B

2. 2 spoons

3. Graduated cylinder

4. Red Liquid

5. Zip lock bag

6. Water

IV. Lab Safety:

· Wear goggles

· Wear apron

V. Data and/or Observations:

Chemical

Description


Solid A

Rocky, chunky, white


Solid B

Powdery, sand-like, thin, white


Red Liquid

Odorless, red, liquid


A

B

Red

Water

Observations


(look on lab to see data table)


VI. Experimental Errors:

Hole in the bag - you would not know when a gas was produced

VII. Conclusion:

The purpose of the Reaction in a Bag lab was to record the observations that occur when multiple chemicals are combined and to use or observations to understand the reaction of the chemicals. When we mixed substance A, substance B, and the red liquid they turned yellow and pink. The pink substance was cold; the yellow substance was hot and the bag filled with gas. I have come to the conclusion that when you combine substance A, substance B, and a liquid are combined there is a color change, temperature change, and a gas is produced. I have come to this conclusion because during the lab the data and my observations have shown when substance A is mixed with a liquid it creates an exothermic reaction, when substance B is mixed with a liquid it creates an endothermic reaction, and when substance A, substance B, and a liquid creates a gas.


Reaction in a Bag POST-LAB

Red Liquid

  • Phenol red
  • used as ph indicator
  • below 7 turns yellow
  • above 8 turns pink


Ph scale

  • mesures acidity
  • goes from 0-14 (acidic - neutral - alkaline)
  • lemon juice - 1.5
  • Tums - 10


2 Solids

  1. Calcium chloride ( calcium + chloride)
  • mildly acidic
  • hydrotropic - attracted to water (absorbs water)
  • uses: canned veggies (Keeps from getting mushy), electrolyte in sport drinks, flavors pickles
  1. sodium bicarbonate (baking soda)
  • not acidic
  • uses: tooth paste, cat litter, in baking, laundry detergent

Heating Baking Soda Lab

I. Purpose: To observe and record the reaction that occurs when baking soda is heated

II. Procedure:

Part 1

1. Put 0.5 cm of baking soda into test tube

2. Set up apparatus

· Fill container to mid line

· Invert bottle without air bubble

· Insert tubing into bottle

· Put stopper into test tube

3. Have Mr. Leeds check set-up

4. Light burner

5. Answer blue dot # 1-3

6. When reaction ends remove the tubing THEN cap flame

Part 2

1. Put 0.5 cm into another test tube

2. Pour tea into both test tubes

3. Compare the color of test tubes

4. Clean up

III. Materials:

1. Peg board

2. Test tubes (2)

3. Rubber band

4. Baking soda

5. Water

6. Container

7. Tea

8. Stopper

9. Rubber tubing

10. Glass bend

11. Burner

12. Matches

13. Clamp

14. Stirring rod

IV. Lab Safety:

Wear goggles Put hair up Wear Apron

V. Data and/or Observations:

Blue dot questions:

1. The test tube looks brown at the bottom.

2. There is water/condensation near the top of the test tube.

3. Water in the bottle is bubbling and then leaving the bottle.

4. I think the gas came from the baking soda heating up.

5. I think that the water droplets came form the water in the bottle.

6. The color in the heated test tube is an orangey yellow and the unheated test tube is a murky orangey brown.

7. The two white substances are not the same because the colors of the tea in the two test tubes are not the same color.

VI. Experimental Errors:

1. Stoppers not secure: if the stopper is not secure the gas would exit the test tube and it would not push the water in the bottle into the container.

2. Large air bubble: if there is a large air bubble in the bottle you may not notice that the gas is pushing the water out of the bottle and into the container.

VII. Conclusion:

The purpose of the heating baking soda lab was to observe and record the reaction that occurs when baking soda is heated. During the lab when the baking soda was heated we saw brown marks at the bottom of the test tube and condensation at the top of the test tube. After the test tube was done heating and we put the tea in it we saw that the color was different than the color of the unheated test tube’s color. I have come to the conclusion that once the baking soda was heated it was no longer baking soda. I have come to this conclusion because during the lab I observed that when we added the tea to the unheated and heated test tubes that they were not the same color so something must have changed in the heated baking soda.

VIII. Extra Question(s):

It is less than the amount of baking soda because if the condensation comes from the baking soda and baking soda is not made up of condensation then the baking soda is more because only some parts of the baking soda make the condensation.


Heating Baking Soda POST-LAB

Blue dot Questions:


  1. Brown on test tube from heating
  2. Condensation at top
  3. Water coming out
  4. the baking soda
  5. come from hot gad touching cooler surface at the top of the test tube and turns it into a liquid
  6. Usually the heated test tube is darker
  7. No, they are different because the color of the heated and unheated test tubes are different.


control group: unheated test tube


experimental group: heated test tube


Indicator: tea (showed that heated and unheated are not the same)


Variable: something you want to measure


Independent variable: cause a change in dependent variable (temp.)


control factors:

  • same type of tea
  • same amount of tea
  • same amount of baking soda
  • same size test tube
  • same amount of time stirring


Experimental Error:

  • Hole in tubing- bottle won't fill with gas


Extra Question:

(look on lab report)


Box Question:

  1. It releases gas when heated, which helps batter to rise. (pg. 5)

Measuring Volume by Displacement of Water Lab

Measuring Volume by Displacement of Water

I. Purpose:

To use the displacement of water method to determine the volume of dry sand is sand and air space.

II. Procedure:

1. Pour sand into yellow cylinder with funnel.

2. Fill clear cylinder with 16 or 17 cm3 of water.

3. Pour sand into water with funnel.

4. Record the volume of sand and water (from level of water)

5. Pour wet sand into bucket (not sink)

III. Materials:

· Sand

· Water

· Bucket

· Funnel

· 2 graduated cylinders

IV. Lab Safety:

N/A

V. Data and/or Observations:

Volume of dry sand

31cm3


Volume of water

16cm3


Volume of sand and water

35cm3


Volume of sand alone

19cm3


Volume of air space

12cm3


Fraction of sand that is air space

0.39


% Of sand that is air

39%


VI. Experimental Errors:

1. If you added the water to the sand instead of the sand to the water the sand would just lay at the bottom and the water would lie on top and the water level would be too high.

2. If you did not add the specific amount of water or sand if would affect all of your calculations

VII. Conclusion:

The purpose of the measuring volume lab was to use the displacement of water method to determine the volume of dry sand is sand and air space. We added a specific amount of sand to water and measured the sand and water. After this we used are data of the sand and water volume to decipher the volume of other substances or two substances put together. I have come to the conclusion that the volume of air space in 31cm3 of sand is 12cm3. I have come to this conclusion because the data calculation showed this in each different group I encountered.

VIII. Extra Question(s):

The purpose of giving the groups different amounts of sand was to show that the percentage of sand that is air changes but some of the other volumes do not.


Sensitivity of the Balance Lab

Sensitivity of the Balance

I. Purpose: To observe if you mass the same objects repeatedly will the mass remain the same. Also, to decipher how different the masses of two objects must be for our balance to detect the difference.

II. Procedure:

Part A:

1. Clean pan and zero the balance

2. Mass penny and stopper alternately

3. Zero balance between each object

4. Do not share until finished all massings

Part B:

1. Zero balance

2. Cut our a 20x20 square

3. Mass the large square

4. Calculate mass of small square

5. Figure out how many squares mass by division

6. Cut out 10 groups of squares

7. Mass a stopper, leave in pen and don’t move riders

8. Add groups of squares one at a time and record the mass that changes

III. Materials:

· Stopper

· Penny

· Balance

· Scissors

· Graph paper

IV. Lab Safety:

N/A

V. Data and/or Observations:

Number

Mass of penny

Mass of Stopper

1

2.411

8.571

2

2.391

8.569

3

2.402

8.552

4

2.409

8.780



Mass of 20x20

0.642

Mass of single square

0.001605

Mass of 4 squares in group

0.00642

# Of group

∆ M (yes or no)

Mass (g)

1

Yes

12.491

2

Yes

12.496

3

Yes

12.501

4

Yes

12.506

5

No

12.506

6

Yes

12.511

7

No

12.511

8

Yes

12.520

9

Yes

12.525

10

Yes

12.529



∆ M

0.038

Number of yes’s

8

Sensitivity

0.00475

Blue Dot Questions:

1. Our balance gave the same result to the 0.01g

2. We do not have any pattern because sometimes we would have four yes’s before a no and sometimes ye would have only one yes before a no.

VI. Experimental Errors:

1. If the pan was dirty was dirty or wet from a past experiment it would have added weight to the object you were weighing.

2. If you cut the squares unevenly or you counted wrong in cutting the squared you would have some heavier and some lighter squares that would throw off how much the balance changes between each measurement.

VII. Conclusion:

The purpose of this experiment was to observe if you mass the same objects repeatedly would the mass remain the same. We repeatedly measured the mass of a stopper and a penny and wrote down their masses. We discovered that every time the mass changes, even when you are measuring the same object. I have come the conclusion that the mass of the object does not change the sensitivity of the balance and the measuring changes the measurement. I have come the this conclusion because the data shown that the measurements are very close to each other but are not exactly the same.

The purpose of this experiment was to decipher how different the masses of two objects must be for our balance to detect the difference. When we measured the paper and then cut it out and measured the change between each paper we discovered that each group of paper had about a 0.00642 mass. I conclude that the paper changed almost every one of our measurements because its mass was added to the mass of the stopper. I have come to this conclusion because the data showed that almost every time we added one of the groups of squares, the mass went up.

VIII. Extra Question(s):


Sensitivity of the Balance Post-Lab

The lightest mass that you can expect the balance to detect is the sensitivity



+- the margin of error when you mass something.


Sensitivities:

.02

.02

.02

.01

.00

.01

.01

.01

.02

.01

.01

The mass of dissolved salt lab

The Mass of Dissolved Water

I. Purpose: To determine if the mass of salt decreases when salt dissolves in water

II. Procedure:

1. Check pan/ zero balance

2. Dry cap, then mass cap

3. Add 2g to the balance

4. Add salt to cap until balanced

5. Fill bottle 2/3 with water

6. Mass bottle with water and cap with salt together but not mixed

7. Pour salt into bottle

8. Shake bottle until all the salt dissolves

9. Mass bottle with cap on

10. Calculate ∆M: Mf-Mi

III. Materials:

· Salt

· Bottle

· Cap

· Water

· Balance

· Scooper

IV. Lab Safety:

N/a

V. Data and/or Observations:

Lab #

Mi (g)

Mf (g)

∆M (g)

1

18.591

18.532

-0.059

2

18.551

18.293

-0.258

VI. Experimental Errors:

1. If you clean the pan between Mi and Mf the salt to water of the pan that was cleaned off would mess up your mass calculations because in the Mf you would not have that extra mass.

2. If the outside to the bottle was wet it would add extra mass to the Mi but once you started shaking it the water would come off on your hand so it would take that mass away from your Mf.

VII. Conclusion:

I conclude that when salt dissolves it reduces the mass of the object. I have come to this conclusion because most of the data of the ten lab experiments shows that tis conclusion is true. I have come


The mass of dissolved salt post-lab

6/10 groups got a decrease in mass


3/10 could have had no change (sense. of balance)


Mass of Copper and Sulfur Lab

The Mass of Copper and Sulfur

I. Purpose: The purpose of the lab is to determine if the total mass of copper and sulfur increases, decreases, or stays the same when heated.

II. Procedure:

1. Clean pan/ zero balance

2. Mass test tube/sheet/band together

3. Mass 2g copper

4. Mass 1g of sulfur

· Mass paper towel size of pan

· Add 1g to the mass

· Add sulfur until the balance is correct

5. Put both substances into the test tube

6. Close the end of the test tube with a rubber sheet held in place by a rubber band.

7. Mass the test tube.

8. Ask Mr. Leeds to check your set up

9. Light burner

10. Wait until mixture glows

11. Remove the flame

12. After cools, mass the test tube

13. Clean up

III. Materials:

· Large test tube

· Sulfur

· Copper

· Rubber Band

· Rubber Sheet

· Balance

· Paper Towel

· Alcohol Burner

· Large Clamp

· Peg Board

· Matches

IV. Lab Safety:

· Tie up hair

· Don’t waft powders

· If you get a chemical on your skin wash it under water and tell Mr. Leeds

V. Data and/or Observations:

Mass of test tube/sheet/band

33.219

Mass of test tube/sheet/band/copper/sulfur unheated

36.171

Mi of copper and sulfur

3.048

Mass of test tube/sheet/band/copper/sulfur heated

26.171

Mf of copper and sulfur

3.048

∆M

0.000

VI. Experimental Errors:

1. If there were a hole in the rubber sheet that you placed on the test tube you would not see the gas that was produced when heating.

2. If the flame was directly under the test tube you may not have noticed the sulfur melting because it may have melted too fast.

VII. Conclusion:

The purpose of the Mass of Copper and Sulfur Lab was to determine if the total mass of copper and sulfur increases, decreases, or stays the same when heated. We measured 2g of Copper and 1g of sulfur into a test tube and heated it over an alcohol burner. After the test tube was heated for a while we started to see a greenish gas start to appear in the test tube. We also saw that the sulfur and copper were melting. I conclude that when copper and sulfur are heated together that they loose mass. I have come to this conclusion because half of the class got no change in mass and a few more were within the sensitivity of the balance.


The Mass of a Gas Lab

The Mass of the Gas

I. Purpose: To observe if the mass will stay the same, increase, or decrease when a solid and liquid produce a gas.

II. Procedure:

1. Clean and zero balance

2. Fill bottle 1/3 with water

3. Mass bottle, cap, and tablet (in cap) (dry cap)

4. Put tablet in bottle (don’t touch with hands)

5. Wait 30 seconds and mass the bottle

6. Slowly loosen cap (Don’t Remove)

7. Mass Bottle

III. Materials:

· Bottle

· Balance

· Alka- seltzer

· Water

· Cap

IV. Lab Safety:

N/A

V. Data and/or Observations:

Bottle/cap/tablet/water (mi)

27.376

28.393

28.419

Bottle/cap/solution (Mf)

27.369

28.382

28.440

∆ M

-0.007

-0.011

-0.021

Mass after gas is released

27.309

28.331

28.344

Mass of the gas

0.060

0.051

0.096

VI. Experimental Errors:

1. If not all the alka-seltzer dissolved before you weighed it for the mass of bottle/cap/water its mass it may have been incorrect because the mass of the alka-seltzer may have decreased or increased the mass.

2. If when you filled the bottle with 1/3 water, some of the water got on the outside of the bottle it would increase the mass.

VII. Conclusion:

The purpose of the lab was to observe if the mass will stay the same, increase, or decrease when a solid and liquid produce a gas. We measured the mass of the bottle, water, cap, and tablet (not dissolved) and then massed it again with the alka-seltzer dissolved. I have come to the conclusion that when you dissolve alka-seltzer the mass decreases. I have come to this conclusion because the majority of the class had a negative ∆M.


The Mass of a Gas post-lab

Alka-seltzer: Antacid and pain reliever



  • ingredients: Aspirin, citric, acid, sodium bicorbonate

Mass and Volume Lab

Mass and Volume Lab

I. Purpose: To decipher if the mass of a 1cm3 object will depend on its shape or the substances it is made of.

II. Procedure:

1. Verify the volume by the displacement of the water

2. Answer blue dot #1

3. Clean/zero balance

4. Mass the 3 cylinders

5. Mass the short Al cylinder

6. Mass brass cylinder

7. Answer blue dots # 2-4,6,7

III. Materials:

1. 3 long Al cylinders

2. 1 short Al cylinder

3. 1 brass cylinder

4. Graduated cylinder

5. Water

6. Balance

V. Data and/or Observations:

Object

Mass

Volume (cm3)

1st long cylinder

2.652 g

1.0 cm3

2nd long cylinder

2.629 g

1.0 cm3

3rd long cylinder

2.607 g

1.0 cm3

Small Al cylinder

2.801 g

1.0 cm3

Brass Cylinder

8.511 g

1.0 cm3

Blue dot Q’s:

1. Yes, because they are all the same size

2. It would be double the mass the first cylinder

3. The volume would be 2cm3

4. Yes, because you can divide the mass

5. N/A

6. Yes it does

7. No it can have the same mass and volume but not both at the same time.

VI. Experimental Errors:

1. If you added too little water and it did not reach over the cylinder it would result in a lower volume.

2. If you mixed up the cylinders order you could have messed up your mass or volume.

VII. Conclusion:

The purpose of the Mass and Volume Lab was to decipher if the mass of a 1cm3 object will depend on its shape or the substances it is made of. During the lab we took the mass and the volume of different cylinders and recorded the data. We saw that the volume did not change. I conclude that no matter the size or which cylinder you use if it is the same amount o metal that the volume will be the same but the mass may be different. I have come to this conclusion because the data shows that the volume was the same for each cylinder.


Density of a solid

Density of a Solid

I. Purpose: to utilize density to determine if 3 metal objects are made of the same substances.

II. Procedure:

1. Try to tell if the two cubes have the same or different mass by picking them up.

2. Clean/zero balance

3. Mass the cubes

4. Answer Blue Dot #1

5. Compare the weight of the cubes to the weight of the slab by picking them up.

6. Answer blue dot #2

7. Mass slab

8. Measure the dimensions of the cubes and slab and calculate volume

9. Calculate density

10. Find volume and mass of an irregular-shaped object

11. Calculate density of rock.

III. Materials:

1. Rock

2. 3 metal objects

3. Balance

4. Water

5. Graduated cylinder

6. Ruler

IV. Lab Safety:

N/A

V. Data and/or Observations:

Object

Length (cm)

Width (cm)

Height (cm)

Cube 1

1.22

1.22

1.22

Cube 2

1.22

1.22

1.22

Slab

7.53

2.53

0.52

Object

Volume (cm3)

Mass (g)

Density (g/cm3)

Cube 1

1.82

5.808

3.19

Cube 2

1.82

16.076

8.82

Slab

9.91

33.762

3.41

Rock

3.0

7.00

2.33

VI. Experimental Errors:

1. If you did displacement of water before massing the rock the rock may have been wet and that would result in an increase in mass.

2. If you mixed up cube 1 and cube 2 you may have the wrong mass with the wrong volume and vice versa. That would result in a wrong density.

VII. Conclusion:

The purpose of this lab was to utilize density to determine if 3 metal objects are made of the same substances. During the lab we calculated the mass and volume of three different metal objects to get the density of those objects. We would use the density to determine it they were made of the same substance. When we did this lab we noticed that none of the density calculations were the same. We have come to the conclusion that none of the metal objects are made from the same substance. We have come to this because, referring to the class data, even though that none of the density numbers are exactly the same for one single object they are all pretty close to density’s of the same object, but the other objects are way too far away from the other metal objects to be the same substance or have the same density.


Density of a Solid post-lab

Histo shows that cube 1 and the slab are most likely the same substance



Density of a liquid

Density of a Liquid

I. Purpose: to use the density to compare 2 liquids to decide if they are the same substances.

II. Procedure:

1. Zero balance/clean

2. Waft liquid

3. Mass empty graduated cylinder

4. Fill graduated cylinder with 10cm3 of liquid

5. Mass graduated cylinder with liquid

6. Pour liquid into sink, rinse cylinder

7. Repeat and with next liquid (re-mass cylinder)

III. Materials:

1. Balance

2. Beaker

3. Liquid A

4. Liquid B

5. Graduated cylinder

IV. Lab Safety:

- Wear apron and googles

V. Data and/or Observations:

Liquid

Mass of empty cylinder (g)

Mass of liquid and cylinder (g)

Mass of liquid (g)

Volume of liquid (cm3)

Density of liquid

A

15.000

26.382

11.382

10

1.14

B

14.821

25.204

10.383

10

1.04

VI. Experimental Errors:

1. If you waited to long in taking the mass of the liquid and cylinder after you filled it some of the liquid may have evaporated making your volume not 10 and your mass too small.

2. If in a past period the sample was contaminated then their may be something in your mass that was not supposed to be there that could increase or decrease your mass.

VII. Conclusion:

The purpose of the lab was to use the density to compare 2 liquids to decide if they are the same substance. We measured the mass of liquid A and the mass of liquid B and we found that the masses were about 1 gram different. I conclude that the two liquids are different because their densities are too far apart. I have come to this conclusion because the class data showed that the two densities are fairly far from eachother.


Density of a Gas Lab

Lab 3.7

I. Purpose: to produce and collect a gas in order to accurately decipher the denstiry of the gas.

II. Procedure:

1. Clean/zero balance

2. Put 5cm3 into test tube

3. Mass the two ½ Alka-Seltzer tablets, tin foil, test tube with 5cm3 of water, and rubber band.

4. Find the Volume of the bottle

5. Set up apparatus

6. Have Mr. Leeds check apparatus

7. Drop 2 ½ tablets into test tube water

8. Put on stopper

9. Insert Tubing

10. Wait 10 mins.

11. Remove delivery tube from collection container.

12. Remove stopper

13. Carefully invert bottle out of water

14. Mass test tube with H2O left in bottle

15. Clean up

16. Calculate density

III. Materials:

1. Balance

2. Water

3. Foil

4. Alka-Seltzer

5. Stopper

6. Test tube

7. Glass bend

8. Rubber tubing

9. 2 rubber bands

10. Container

11. Peg board

12. Bottle

13. Clamp

14. Graduated cylinders

IV. Lab Safety:

Wear safety goggles

V. Data and/or Observations:

Mi (g)

Mf (g)

∆M (g)

Vi (cm3)

Vf (cm3)

∆V (cm3)

Density (g/cm3)

39.164

38.533

-0.0531

534

303

-231

2.3 x 10-3

VI. Experimental Errors:

1. If you touched the Alka-Seltzer after the Mi it would result in a loss in mass because some of it may come off on your hands.

2. If you forget to place the tinfoil back onto the balance for the Mf because it was not there during the Mi.

VII. Conclusion:

The purpose of the lab was to produce and collect a gas in order to accurately decipher the density of the gas. We massed and got the volume of the objects and found that they both decreased after the experiment was done. I conclude that the density of the gas is 0.0022 or 0.0021 because after the experiment we divided the mass by the volume and most of the class data were in these columns. I have come to this conclusion because the class data showed this.