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WLHS Science DepartmentMr. Matt Bilitz & Mr. Mike Sebald

Chemistry Lab Manual

Quarter 1

1. Graduated Cylinders

a. Obtain two graduated cylinders: 100 mL and 10 mL. What is the smallest volume increment marked on each cylinder?

b. Half fill each cylinder with water. Notice the shape of the surface of the water. Sketch a drawing of the shape of the water surface. This is called the meniscus. Always read the level of the liquid at the bottom of the meniscus.

c. Write down the measurement of the liquid you have placed in each cylinder. Remember to estimate the last digit.

Lab 1-1: Measurement in Chemistry

Equipment:

BalanceBunsen burner100 mL graduated cylinder10 mL graduated cylinderMetric ruler400 mL beaker250 mL beaker150 mL beakerWire gauzeThermometerCrucible Tongs

Safety: Although there are no specific hazards involved with this lab, you must wear safety goggles and apron. (besides, it looks cool).

Materials:

Metal cylinderWaterWeighing Paper

IntroductionMost chemistry lab activities involve the use of various measuring instruments. The three variables you will measure most are mass, volume and temperature. Failure to obtain a satisfactory result in a lab is usually the result of improper or inaccurate use of measuring instruments. In this activity you will become familiar with the measuring instruments most often used in chemistry.

2. Laboratory Balance

a. The top loading balance used in chemistry is a sensitive instrument that can be easily damaged if used improperly (which, by the way, will incur the wrath of your chemistry teacher). What are the precautions you must take to prevent damage to this (very expensive) instrument?

b. Place three items (pen, coin etc.) one at a time on the balance and record the mass of each.

c. Use a different balance to mass the same three items. Is there a difference?

d. Place a piece of weighing paper on the balance. Press the zero (tare on some balances) button. What happens? How can this be useful in measuring dry chemicals?

3. Ruler

a. Obtain a centimeter ruler. What is the smallest increment on the ruler? Be sure you are using the centimeter side of the instrument.

b. Measure four different items and record the length. Be sure to estimate the last digit.

c. Obtain a metal cylinder. Measure the diameter and height. Calculate the volume of the metal cylinder.

4. Beaker

a. Obtain a 400 mL, 250 mL and 150 mL. How far do the markings on each instrument go?

b. Place 100 mL of water in the 400 mL beaker using the markings on the beaker as your guide. Pour the water into a 100 mL graduated cylinder (if the water appears to be more than 100 mL, stop at 100 mL, pour out the water and determine the remaining amount of water with the graduated cylinder. Add to 100 mL). Record the volume. Repeat this with the 250 mL and 150 mL beakers.

c. Calculate the percent error for each of the beakers. Your instructor will give you the formula for percent error. Assume the volume in the graduated cylinder is the true volume.

d. What does the percent error tell you about the accuracy of the markings on a beaker?

5. The Bunsen Burner

a. Put on your safety goggles

b. Light the Bunsen burner according to the instructions given by your teacher. Open and close the air window gradually and note how the shape of the flame changes. Why does this happen? Sketch a diagram of each type of flame?

c. In what situations would you use each of these flames?

d. Test the temperature in the different zones of a hot flame (air window open) by holding a wire gauze (one without the white center) horizontally with a crucible tongs about 1 cm above the burner (see diagram). Note color and appearance of gauze. Now move it up through the flame until it no longer glows.

e. Position the wire gauze vertically in the flame. This shows a vertical profile of the temperature regions of the flame. Sketch a profile of the flame and label the “cool” and “hot regions.

f. Close the air window and repeat steps d & e.

6. Thermometer

a. (Caution: Many of our lab thermometers contain mercury. Mercury can be a dangerous substance if it not handled properly. Thermometers are very easily broken. If a mercury thermometer breaks, inform your instructor immediately.) Place about 100 mL of water in a 250 mL beaker. Measure the temperature of the water.

b. Place the beaker on the ring stand and begin heating the water strongly with your Bunsen burner. Measure the temperature of the water at one-minute intervals for 5 minutes. Discard water.

Pre-lab questions. (Answer these questions in your laboratory notebook. Use complete sentences.)

1. What is the difference between quantitative and qualitative observations?2. Scientists, if possible, work with quantitative measurements. Why?3. What is the difference between weight and mass? Which will we be measuring in lab

activities?

4. A student recorded the temperature of boiling water as 100 oC. Her partner recorded the same measurement as 100.0 oC. Which is the correct way of recording the measurement? How many significant figures does each of these measurements have?

5. Why must mercury thermometers be handled with care? What should you do if a mercury thermometer should break (hint: “run about the room screaming” is not the correct answer)?

Data (record the following data in your laboratory notebook)

1. Graduated Cylinder

a. Smallest volume increment: 100 mL ____________________ 10 mL ____________b. Sketch of meniscus:c. Measurement of each liquid volume: 100 mL ____________ 10 mL ____________

2. Laboratory Balance

a. Precautions:b. Item 1 _______________ Mass _________

Item 2 _______________ Mass _________Item 3 _______________ Mass _________

c. Item 1 _______________ Mass _________Item 2 _______________ Mass _________Item 3 _______________ Mass _________

d. How can this be useful?

3. Ruler

a. Smallest increment of ruler _______________

b. Item 1 _______________ Length ___________Item 2 _______________ Length ___________Item 3 _______________ Length ___________Item 4 _______________ Length ___________

c. Volume of the metal cylinder (show your work with units):

4. Beaker

a. How far do the markings on each instrument go: 400 mL _______ 250 mL________ 150 mL __________

b. The actual volume of 100 mL of water in: 400 mL ________ 250 mL _________ 150 mL _________

c. Percent error for each beaker: 400 mL ___________ 250 mL __________ 150 mL __________

d. Make a statement regarding the accuracy of marking on a beaker.

5. The Bunsen Burner

b. What happens to the flame? Sketch a diagram of each type.c. In what situations would you use each type of flame?e. Diagram:f. Diagram:

6. Thermometer

a. temperature of the water ____________b. record data for heating water:

Conclusion (Answer the following questions in your laboratory notebook. Use complete sentences.)

1. If you were asked to measure exactly 100.0 mL of water what instrument would you use?2. If you were asked to measure about 200 mL of water what instrument would you use?3. Why should you use the same balance for an entire lab activity?4. Why should chemicals never be weighed directly on the pan of the balance?5. Explain, step by step, how 5.0 g of a dry chemical should be massed on a balance.6. Explain, step by step, how 5.0 g of a liquid chemical solution should be massed on balance.

Extra Credit: You will have the opportunity to earn up to two points of extra credit for each lab if you provide a Bible passage that would be appropriate for the activities of the lab activity. The Bible passage must have a full reference (i.e. Job 38: 4-5 NIV) and an explanation that ties the passage into the lab activity. Since I am a nice guy, I will do the first one for you:

Job 38: 4-5 NIV

3 Brace yourself like a man; I will question you, and you shall answer me.  4 "Where were you when I laid the earth's foundation? Tell me, if you understand.  5 Who marked off its dimensions? Surely you know! Who stretched a measuring line across it?

Explanation: This reminds me that our creator God is in control of the universe. He knows the dimensions of the universe down to the smallest microbe. Mankind’s knowledge of science is infinitely small compared to the almightily God.

Procedure:

1. Cut four rectangular pieces of aluminum foil. Be sure that the dimensions are at least 9.0 cm on each side. (this step may already be done by a previous class).

2. Carefully measure the length and width of each piece of foil. Record the measurements on the Report Sheet. Remember that the last digit in your measurement is an estimated digit.

3. Find the mass of each piece of foil. Record the mass of each sheet on your Report Sheet.

4. Put materials away and begin calculations.

Lab 1-2: The Thickness of a Thin Aluminum Sheet

Introduction:In science, we make use of large and small numbers many times. In addition, we must often use one set of measurements and known properties to indirectly measure other quantities. One example of this type of “measurement” will be found in this experiment. The tools necessary to measure the thickness of a piece of aluminum foil would not normally be found in a chemistry laboratory. We, however, will be able to indirectly measure the thickness through a series of measurements and calculations. You are probably wondering why it is important to know the thickness of aluminum foil. Well, guess what? It isn’t important. What is important is that you are able to use measuring instruments with accuracy. The other purpose of the lab is to apply the rules of significant figures and scientific notation properly.

Safety Considerations:

There are no special safety considerations.

Materials:

4 pieces of aluminum foilcentimeter rulerbalance

The Thickness of a Thin Aluminum Sheet

Pre-lab questions: Put the following equations in the pre-lab section of your lab notebook

The formulas that will enable you to find the thickness of the foil are familiar to you:

The volume of a regular object is found using the formula:

V =

Imagine that the regular object is a rectangular shaped piece of foil and that the height of the foil is the thickness (T). The formula could be written as:

V =

Going one step further, the area of the foil can be expressed as A = l x w, so our formula for volume can be restated as:

V =

Since the experiment involves finding thickness, it would be better to rearrange the formula once again. Dividing both sides of the equation by A, we get the new equation:

T = (Equation 1)

++++++++++++++++++++++++++++++++

Our next problem will be to find the volume and area of the piece of foil. We can do that indirectly using the known property of density. The formula for density is:

D =

The density of aluminum is a known property, and the mass of the foil can be measured with a balance. The volume of the aluminum foil can then be calculated by using the rearranged equation:

V = (Equation 2)

Pre-lab questions: (Answer these questions in your laboratory notebook. Use complete sentences or show calculations.)

1. Do the calculations in the following problems. Use the following format:Formula

Substitute numbers into formula with unitsRaw answer

Answer with correct number of significant digits.

A thin piece of lead foil has the following dimensions:

l = 8.20 cm w = 2.25 cm

a. Calculate the area of the piece of lead.b. If the density of lead is 11.35 g/cm3, and the mass of this sample is 18.25 g, what is the

volume of the sample?c. Using the above information calculate the thickness (in centimeters) of the lead (express

your answer in scientific notation).

2. Define the scientific meaning of precision and accuracy (use a reference book if necessary).

3. A student made the following measurements of thickness of three pieces of aluminum metal that came from the same sheet: 0.0127 cm, 0.0125 cm, 0.0123 cm. The known thickness based on manufacturer data was 0.00295 cm. Comment on the precision and accuracy of the measurements.

Data (record the following data in your laboratory notebook)

1. Reproduce the following data table in your lab notebook. Note that I have not included units. Make sure your data table includes appropriate units.

Data Table 1

Sheet # Length Width MassABCD

2. Instructions for Data Table 2: Using the above table as a guide, construct a data table that shows area, volume and thickness for each foil sheet. Refer to the pre-lab questions for the formulas to be used. Your numbers should be rounded to the correct number of significant figures. The thickness measurement should be recorded in scientific notation. (Hint: you will need to find the density of aluminum from a reference book.)

3. Show how you calculated area, volume and thickness for sheet A below Data Table 2.4. Compare your thickness calculations with two other groups. Make a general statement as to

how your thickness calculations compare? 5. What information would you need to have to determine the accuracy of your measurements?

How precise are your answers

Conclusion (Answer the following questions in your laboratory notebook. Use complete sentences or show a logical progression of calculations.)

1. Could the method used in this lab to determine the thickness of the foil be used to determine the thickness of an oil spill (hint: I wouldn’t ask this question if the answer was no). What information would be needed?

2. A very thin layer of gold plating was placed on a metal tray that measured 25.22 cm by 13.22 cm. The gold plating increased the mass of the plate by 0.0512 g. Calculate the thickness of the plating (The density of gold is 19.32 g/cm3). (Show your work)

3. During a chemistry pool party a quart (1.0 qt) of oil was accidentally dumped into the swimming pool. The swimming pool measures 25.0 m by 30.0 m. How thick was the resulting oil slick (assume the oil spreads out evenly over the entire surface of the pool). (Hint: 1.06 quarts = 1000 cm3).

Lab 2-1: Specific Heat of a Metal

Materials:

Goggles & ApronBurner with ring stand250 mL beakerBalanceMetal SamplesFoam cup calorimeterThermometerCrucible tongs

Safety Considerations:Goggles and aprons must be worn for this experiment. Before you light the burner long hair and loose clothing must be confined. Allow all apparatus to cool before handling it.

Introduction:Chemists identify substances on the basis of their chemical and physical properties. One physical property of a substance is the amount of energy it will absorb per unit of mass. The property is called specific heat (Cp). Specific heat is the amount of energy, measured in joules (J), needed to raise the temperature of the substance one Celsius degree. To measure specific heat in the laboratory, a well-insulated container called a calorimeter will be used. To the ordinary, untrained person, the calorimeter will look like a Styrofoamâ cup. To us cool chemistry-type people this will be a scientific instrument. The calorimeter is insulated to reduce loss or gain of heat energy from the surrounding environment. Energy always flows from an object at a higher temperature to an object of lower temperature. If we assume no loss of heat to the surrounding environment, the heat gained by the cooler substance is equal to heat lost by the warmer substance. Thus:

Heat Lost by Metal = Heat Gained by Water

In this experiment, you will determine the specific heat of the metal sample. You will be using the following equation:

Mass of metal x DT of metal x Cp of Metal = Mass of water x DT of water x Cp of water

Procedure:

1. Put on goggles and aprons.2. Fill a 250 mL beaker about ¾ full of tap water. Place the beaker of water on the ring stand

with wire gauze. Begin heating the water to the boiling point.3. While the beaker is being heated record the mass of a metal sample.4. Record the mass of the foam calorimeter (to the untrained eye it looks like a Styrofoam

cup…but it’s not).5. Fill calorimeter about ¼ (about 50 mL) full of water. Mass and record.6. When the water in the beaker is boiling place one of the samples of metal into the boiling

water. Wait about 4-5 minutes for the metal to achieve the same temperature as the water (it will be assumed that the temperature of the metal is the same as the temperature of the water). Record the temperature of the metal. Helpful Hint: Continue to heat the boiling water for the second and third trials.

7. Cool the thermometer and measure the temperature of the water in the calorimeter and record.

8. Using crucible tongs, quickly remove the metal from the boiling water and place into the foam cup (oops….I mean calorimeter).

9. Using a cool thermometer, stir the water in the calorimeter gently (thermometers can be easily broken which will incur the wrath of Sebald/Bilitz). Record the highest temperature reached by the water.

10. Recover the metal by carefully pouring off the water. Dry the metal sample with a paper towel.

11. Repeat the entire procedure with two different metals. Helpful Hint: In order to maintain accuracy, the water in calorimeter must be massed and the temperature taken for each trial.

Pre-Lab Questions: (Answer these questions in your laboratory notebook. Use complete sentences or show calculations)

1. Rearrange the equation given in the Introduction to solve for specific heat (Cp) of the metal.

2. Using the equation in Question 3 above, set up the following problem to get an answer of 2.50 J/goC: A piece of unknown metal with a mass of 14.9 g is heated in boiling water to 100.0 oC and dropped into 75.0 g of water at 20.0 oC. The final temperature of the system is 28.5 oC. What is the specific heat of the metal?

3. A piece of unknown metal with a mass of 81.0 g is heated to 120.0 oC and dropped into 90.0 g of water at 10.5 oC. The final temperature of the system is 20.0 oC. What is the specific heat of the metal? What metal could this possibly be?

4. Which substance needs more energy to undergo an increase of 10 oC, something with a high or with a low specific heat? Explain.

Data and Calculations:

Reproduce the following data table in your laboratory notebook:

Metal Mass Metal (g)

Metal Start Temp (oC) (Note 1)

Metal End Temp. (oC)(Note 2)

Water Start Temp. (oC)Calorimeter

Water End Temp. (oC)Calorimeter

Mass Calorimeter (g)

Mass Water + Calorimeter (g)

Mass Water (g)

Note 1: Same as boiling water Note 2: Same as Water End Temp. Calorimeter

Conclusion: (Answer the following questions in your laboratory notebook. Use complete sentences)

1. Calculate the specific heat of each of the metals you used in the experiment (show your work with all units).

2. Find the true value for each of the metals and calculate the percent error for each.

3. What are two possible sources of error in this experiment (“wrong calculations” “incorrect massing”…etc. will not be accepted)?

4. Explain how the relatively high specific heat of water contributes to: body temperature regulation; climate near large bodies of water (i.e. Lake Michigan).

Lab 2-2: Physical and Chemical Change

Equipment:BalanceBunsen burnerTest tubesTest tube holderWatch glassMicrospatulaDropper pipetteSafety gogglesLab apronMortar & Pestle

Safety Considerations:Goggles and aprons must be worn. When heating a substance in a test tube, be sure to point the open end of the tube away from others. Handle acids with caution. Acids will burn skin and clothes. Before you light the burner, long hair and loose clothing must be confined. Allow all apparatus to cool before handling it.

Materials:Copper sulfate pentahydrate (CuSO4 · 5H2O)Sodium chloride (NaCl)Hydrochloric acid (6 M HCl)Silver nitrate (0.1 M AgNO3)Sulfur (powdered)Iron filings (Fe)PaperCandleMagnesium ribbon (Mg)Wood splintCalcium chloride (CaCl2)

IntroductionMuch of chemistry involves the study of matter and the changes it undergoes. These changes can be divided into two types: physical changes and chemical changes. In a physical change, size, shape, color, and phase (solid, liquid, gas) may change but no new substances are formed. Grinding, melting, freezing, and dissolving are all physical changes.A chemical change results in the formation of new substances that differ in the chemical properties of the original substances. The burning of wood and the rusting of iron are examples of chemical changes.In this lab you will be doing a series of experiments that involve changes. You need to identify which changes are chemical and which changes are physical.

Procedure:

1. Put on goggles and apron. Note and record all observations in your data table.2. Using a spatula, place 4-5 crystals of CaCl2 (calcium chloride) on a watch glass. Allow to sit

for 20 minutes. Proceed with step 3 while waiting. Disposal: CaCl2 may be washed down the drain when you complete your observations.

3. Light a candle and observe the flame carefully. Quickly (so it doesn’t catch fire) position a 3 x 5 index card vertically in the flame. Perform this procedure several times to obtain a profile of the flame. Disposal: Allow to cool. Dispose of card in waste basket.

4. Break a wood splint into several pieces and place the pieces in a test tube (use an old crudy test tube…not a clean one). Hold the test tube with a test tube holder and heat the test tube for several minutes with a Bunsen burner (hold test tube on an angle). Allow the tube to cool (you may proceed to step 5 while waiting for contents to cool). Empty the contents of the test tube on a piece of paper and observe. Disposal: Allow to cool. Dispose of materials in waste basket.

5. Add a microspatula of NaCl (sodium chloride) to about 5 mL of water in a small test tube. Shake the contents. Next, add about 5 drops of 0.1 M AgNO3 (silver nitrate) to the water-NaCl mixture. Caution: Silver nitrate will stain your skin and clothes. Disposal: Contents may be dumped down the drain.

6. Obtain a piece of magnesium ribbon from your wise and awesome instructor. Tear the ribbon into small pieces and place in a clean test tube. Add a few drops of 6 M HCl (hydrochloric acid) Caution: use extreme care with this acid. It will burn you if it comes in contact with your skin….no kidding. Touch the bottom of the test tube with your with your finger. Disposal: Liquid portion should be dumped down the drain. Any leftover magnesium should be rinsed with water in put in wastebasket.

7. Use a mortar and pestle to grind several crystals of CuSO4 · 5H2O into a uniform powder. Put the powder into a test tube and heat gently for about 1 minute or until you see a color change. Allow the sample to cool. Add two drops of water. Disposal: Contents may be dumped down drain.

8. (Instructor may demonstrate this step) Measure out about 0.50 g of iron filings and 0.50 g of powdered sulfur. Mix the two in a cruddy test tube. Heat the mixture in a strong flame for several minutes. Allow the sample to cool and examine it by probing it with a microspatula. Disposal: Allow to cool. Dispose contents in wastebasket.

Pre-lab Questions:

1. State in your own words the purpose of the lab?

2. What chemicals used in this lab be handled with caution? Why?

3. What are some characteristics that would indicate a chemical change has taken place?

4. What are some characteristics that would indicate a physical change has taken place.

Observations:Record all observations for each step of the procedure in your laboratory notebook.

Conclusion

1. Indicate whether the following changes are physical or chemical. State what observations support your conclusion.

2. Chemical changes involve the formation of “new” substances. Describe the new substances formed in each of the chemical changes you have identified above.

3. The following changes do not always indicate a chemical change. Give examples in which they might be a result of a physical change:

a. change of colorb. apparent loss of massc. apparent disappearance of a substance

a. melting of candle waxb. burning a candlec. breaking of woodd. burning woode. dissolving NaClf. mixing of NaCl and AgNO3

g. tearing of Mg ribbonh. adding HCl to Mgi. grinding of CuSO4 · 5H2Oj. heating CuSO4 · 5H2Ok. mixing Fe and Sl. heating Fe and Sm. calcium chloride and “air”

Materials:

Balance distilled waterCentimeter Ruler metal cube10 mL Graduated Cylinder metal pellets100 mL Graduated Cylinder unknown liquids A & B50 mL Beaker irregularly shaped solids

section of glass rod

Lab 2-3 Density Determination

IntroductionChemistry is the study of matter, which usually is defined as anything with mass and volume. You have already measured the mass and volume of various materials in previous labs. In this experiment you will measure the mass and volumes of different materials using direct and indirect methods. You will also use the mass and volume to find the density of substances.

Volumes of liquids can be measured directly with a graduated cylinder. Volumes of liquids are usually expressed in mL. The volumes of regularly shaped objects, such as a cube, can be calculated by multiplying its length, width and height. Volumes of solids are usually expressed in cm3.

Many solids, such as rocks, do not lend themselves to direct measurement. Volumes of these solids can be measured by water displacement. If a solid is placed in water, the solid will push aside, or displace, a volume of water equal to its own volume. Thus, each milliliter of water displaced is equal to one cubic centimeter of solid volume.

The purpose of this lab is to use your measuring skills and techniques learned in earlier labs to find the mass and volume of different substances. You will use this data to calculate the densities of these substances. It goes without saying that all measurements and calculations will be done using the rules of significant figures.

Safety Considerations:

Safety goggles and aprons must be worn. The liquids used may be flammable and/or poisonous.

Procedure:

A. Glass Rod1. Measure and record the length and diameter of the section of glass rod. Are you estimating

the last digit?

2. Measure and record the mass of the glass rod.

3. Fill a 10 mL graduated cylinder to the 7.00 mL mark. Put the section of glass rod into the graduated cylinder. Read and record the new water level.

B. Irregularly Shaped Objects

4. Find the mass of each of two irregular objects (rock, marble, etc.). Fill a 100 mL graduated cylinder with about 50 mL of water. Record the exact measurement (are you estimating the last digit?). Find the volume of two irregularly shaped object using water displacement (NOTE: do not drop the object into the water. Slide it down the side of the graduated cylinder so as not to break the bottom of the cylinder). Record all measurements.

C. Metal Cube

5. Obtain and measure the dimensions and the mass of a metal cube.

6. Using a 100 mL graduated cylinder find the volume of the metal cube by water displacement (see note above).

D. Metal Pellets

7. Measure and record the mass of a 50 mL beaker. Carefully pour a sample of metal pellets into the beaker. Measure and record the combined mass of the beaker and pellets.

8. Using a 100 mL graduated cylinder, find the volume of the pellets using water displacement.

9. Remove the pellets from the water by placing a paper towel on the screen in the water trough and pouring the pellets on the paper towel to drain the water. Dry the pellets with a dry paper towel and return to the test tube.

E. Liquids

10. Measure and record the mass of a clean, dry 10 mL graduated cylinder.

11. Add exactly 10.00 mL of distilled water to the cylinder. Measure and record the combined mass of the cylinder and water. Clean and dry the cylinder.

12. Repeat step 11 for two unknown liquids.

Pre-lab Questions

1. Write the equation for density with units (unit analysis).

2. Rearrange the equation in number 1 above to solve for mass and then for volume.

Do the calculations in the following problems. Use the following format:Formula

Substitute numbers into formula with unitsRaw answer

Answer with correct number of significant digits3. What is the density of a piece of metal that has a mass of 25.0 g and a volume of 3.89 cm3?

4. What is the volume of a gas that has a mass of 12.560 g and a density of 0.0999 g/cm3?

5. Gasoline has a density of 0.67 g/cm3. What is the density of gasoline in lb/gal? If an automobile has a gas tank that holds 21.0 gallons, how many pounds does the gasoline weigh? Will gasoline float or sink in water? Why?

6. In the opening scenes of the movie, Raiders of the Lost Ark, Indiana Jones tries to remove a gold idol from a booby-trapped pedestal. He replaces the idol with a bag of sand. According to my top-secret scientific calculations the idol had a volume of about 1.0 L. If the density of gold is 19.32 g/cm3, what mass of sand should he have used (report your answer in grams and in pounds). Assuming the density of sand to be 3g/cm3, what volume of sand (in liters) should he have used? Did he have a reasonable chance of not activating the mass sensitive booby trap? (Interesting side note: I was asked to play the part of Indiana Jones, but I said no due to inaccurate scientific information).

Data:

Record all the variables you have measured in a neat and organized manner in your lab notebook. Be sure to record units and use correct significant figures:

Glass Rod:

Irregularly Shaped Objects:

Metal Cube:

Metal Pellets:

Liquids

Calculations: (show work along with ALL appropriate units)

Calculate the volume of the glass rod by water displacement and by direct measurements

Calculate the volume of the metal cube by water displacement and by direct measurements.

Calculate the density of each of the items and liquids you measured

Conclusion:

1. Of the two methods of finding the volume of the cube and glass rod, which is more accurate? Justify your answer.

2. Using a reference book, identify the metal in the pellets and cube (these are common metals). Are they the same metals?

3. One of the unknown liquids is methanol (0.79 g/mL). The other unknown liquid is vegetable oil (0.92 g/mL). Calculate the percent error in your measurements.

4. Explain, in terms of density, why pouring water on a gasoline fire is usually considered a bad idea.