Experiment: Physical and Chemical Properties and ChangesColorTable 2 (complete table)ObservationCh100: Fundamentals for Chemistry 1Instructor: Tony Zable Name:_________________________Experiment: Physical and Chemical Properties and ChangesObjectiveso Identify various physical and chemical properties of mattero To distinguish between chemical changes and physical changes.Materials NeededEquipment: o Hot plateo 250 mL and 500 mL beakerso Glass stirring rodo 12-Well plateo Eyedropperso Microspatulao Evaporating disheso IceChemicals:o Various elements and compoundso Iodine crystalso Sucrose crystalso Acetoneo Steel woolo Cupric sulfate pentahydrate crystalso 10% sodium carbonate solutiono 10% sodium sulfate solutiono 6 M HClo 10% calcium chloride solutiono 10% sodium chloride solutiono Sodium metalo Phenolphthalein solutiono De-ionized waterDiscussionChemistry is the study of matter. It is very common for a chemist to need to describe a bit of matter as thoroughly as possible. In doing so, the chemist would certainly list physical properties. Many physical properties can be observed using our senses; color, crystal shape, and phase at room temperature are some examples. Other physical properties involve quantitative observations and so must be measured; density, specificheat capacity, and boiling point are three examples. A physical change is any change ina substance that does not involve a change in its chemical composition. During a physical change, no new chemical bonds are formed, and so the chemical composition remains the same. Examples of physical change are boiling, freezing, expanding, and dissolving.Matter can also be characterized by its chemical properties. The chemical properties of a substance include all the chemical changes possible for that substance. A chemical change is one in which the substance is transformed to a new substance. That is, there is a change in the chemical composition of the substance. During a chemical change, the atoms are pulled apart from one another, rearranged, and put back in a new arrangement. Examples of chemical change are burning, rusting, fermenting, and decomposing.In this experiment, you will first identify and record various physical properties of substances, using both qualitative and quantitative observations. In the second part, you will look at changes in matter and determine if they are physical or chemical.ProcedurePart A: Physical Properties1. Examine the various substances provided by your instructor and record your observations in Table 1 of the report sheet (Note: some substances may be toxic. Asa precaution, do not open any containers with out the permission of your instructor.)2a. Place a small crystal of iodine in a well of one well-plate and a small crystal of sucrose in a well of a second well-plate. Use an eyedropper to fill each well with distilled water and stir gently with a microspatula. Record whether each substance is completely soluble, partially soluble, or insoluble. Rinse the iodine into a designated waste container and the sucrose into the sink.2b. Repeat the procedure using acetone as the solvent. You may need to rinse the iodine into another designated waste container (ask your instructor). The sucrose can be rinsed into the sink with water.Part B: Physical and Chemical ChangesComplete Table 2 of the report sheet for each of the following systems.1. Inspect a small piece of steel wool. Place it in an evaporating dish, and heat on a hotplate set to high. Allow the system to cool to room temperature. Observe and record any changes in the steel wool.2. Inspect some cupric sulfate pentahydrate crystals, CuSO4.5H2O. Place a few crystals in an evaporating dish and heat on a hot plate set to medium. Observe and record any changes in the salt. After the system has cooled to room temperature, add a fewdrops of water to the crystals. Observe and record any changes.3. Place a few drops of a 10% sodium carbonate solution, Na2CO3, in one well of a well-plate and a few drops of a 10% sodium sulfate solution, Na2SO4, in a second well of the same well-plate. Add 2 or 3 drops of 6 M hydrochloric acid to each well. Observeand record any changes.4. Place a few drops of a 10% sodium chloride solution, NaCl, in one well of a well-plate and a few drops of a 10% calcium chloride solution, CaCl2, into a second well of the same well-plate. Add several drops of a 10% sodium carbonate solution to each well. Observe and record any changes.5. Inspect some iodine crystals, I2. Place a few of the crystals in a dry 250 mL beaker and cover with an evaporating dish that contains ice, as shown in figure 2. In a fumehood, place the beaker on a hot plate set to medium. Observe and record any changes.To be performed by the instructor:6. Fill a 500 or 1000 mL beaker about a third full with de-ionized water. Add a couple drops of phenolphthalein to the water. Gently cut a small piece of sodium metal and place it on a small section of filter paper. Place the filter paper, with metal on top, onto the surface of the water. Quickly cover the beaker with a large watch glass. Observe and record any changes.Report SheetPart A: Physical PropertiesTable 1 (complete table)Name of SubstanceChemical FormulaPhase at Room Temperature ColorOther Physical Properties ObservedElement or Compound?FIGURE 12. SolubilityIodine in water _________ Sucrose in water _________Iodine in acetone _________ Sucrose in acetone _________Part B: Physical and Chemical ChangesTable 2 (complete table)Procedure ObservationPhysical Change orChemical Change? Evidence or Reasoning1. steel wool + heat2a. CuSO4.5H2O + heat2b. CuSO4 + H2O3a. Na2CO3 + HCl3b. Na2SO4 + HCl4a. NaCl + Na2CO34b. CaCl2 + Na2CO35. I2 + heat6. Na (metal) + H2OQuestions1. Distinguish between a qualitative observation and a quantitative one. Give an example of each from this experiment.2. Classify the following properties of sodium metal as physical or chemical:a. Silver metallic color _______________b. Turns gray in air _______________c. melts at 98oC _______________d. Reacts explosively with chlorine _______________3. Classify the following changes as physical or chemical:a. steam condenses to liquid water on a cool surface _______________b. baking soda dissolves in vinegar, producing bubbles _______________c. mothballs gradually disappear at room temperature _______________d. baking soda loses mass as it is heated _______________4. What are some of the ways
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