Experiment: Physical and Chemical Properties and ChangesColorPolar or Non-PolarObservation(s)Ch100: 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 NeededCh100: Fundamentals for Chemistry 2Instructor: Tony Zable Name:_________________________Equipment: o Hot plateo Glass stirring rodo 12-Well plateo Eyedropperso Microspatulao Evaporating dishesChemicals:o Various elements & compoundso Iodine crystalso Sucrose crystalso Acetoneo Steel woolo Cupric sulfate pentahydrate crystalso 10% sodium carbonate solutiono 10% sodium sulfate solutiono 1 M HClo 10% calcium chloride solutiono 10% sodium chloride solutiono De-ionized waterCh100: Fundamentals for Chemistry 3Instructor: Tony Zable Name:_________________________IntroductionChemistry is the study of matter. The most thorough description of a sample of matter will usually begin by observing relevant physical properties, both intrinsic and extrinsic. Many physical properties are qualitative such as color, crystal shape, and phase at room temperature. Other physical properties are quantitative (must be measured) such as density, specific heat capacity, and boiling point. Any change is a substance or sample is considered to be a physical change when its chemical composition is not altered, e.g. boiling, freezing, expanding, and dissolving.Matter can also be characterized by its chemical properties. The chemical properties of a substance include possible ways it can interact with other matter and transform into new substances. When the chemical composition of a substance changed it is referred to as chemical change. During a chemical change, atoms are pulled apart from one another then rearranged to form new substances. Examples of chemical change are burning, rusting, fermenting, and decomposing.In this experiment, you will first identify and record various physical properties of substances. In the second part, you will look at changes in matter and determine if they are physical or chemical.Preliminary Questions1. 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 _______________2. Classify the following changes as physical or chemical:a. Magnesium burns forming a white powder _______________b. Soda water is poured into a glass producing bubbles _______________c. Concrete expands on a hot sunny day _______________d. Bread dough “rises” when yeast is added _______________Ch100: Fundamentals for Chemistry 4Instructor: Tony Zable Name:_________________________Part A: Physical Properties1. Examine the various substances provided by your instructor and record your observations in Table 1. Note: some substances may be toxic. As a precaution, do not open any containers with out the permission of your instructor. Table 1: Physical Properties (complete table)Name ofSubstanceChemicalFormulaPhase atRoomTemperature ColorOther PhysicalPropertiesObservedElement,Compoundor Mixture?2. Solubility is an intrinsic physical property that describes whether a substance (solute), is dissolvable in a liquid (the solvent). This easily observed property can often suggest profound information regarding molecular structure of a substance. For example, a substance is readily soluble in water, which is a highly polar molecule due to the presence of 2 oxygen-hydrogen chemical bonds, is likely to: (i) be either an ionic compound (consisting of ions) or (ii) at least contain strongly polar regions within its molecular structure.Substances that are insoluble in water yet soluble in non-polar solvents such as acetoneare most likely non-polar in structure. Exceptions to these generalizations include substances that are soluble in both polar and non-polar solvents such as alcohols. These types of substances, referred to as amphipathic, have prominent polar and non-polar molecular structures.In this section you will explore the solubility of 2 substances in polar vs non-polar solvents.a. Place a small crystal of iodine in one well of a 12 well-plate and a small crystal of sucrose in a second. 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. The iodine should be disposed of into a waste basket and the sucrose into the sink with water.b. Repeat part (a) using acetone as the solvent.Ch100: Fundamentals for Chemistry 5Instructor: Tony Zable Name:_________________________ Table 2: Physical Properties - SolubilityName of Substance Solvent SolubilityPolar or Non-PolarOther PhysicalPropertiesObservedPart B: Physical and Chemical Changes1. 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 in Table 3.2. 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.Table 3: Physical and Chemical ChangesProcedure Observation(s)Physical Change orChemical Change?Evidence orReasoning1. steel wool + heat2a. CuSO4.5H2O + heat2b. CuSO4 + H2O3a. Na2CO3 + HCl3b. Na2SO4 + HCl4a. NaCl + Na2CO34b. CaCl2 + Na2CO35. I2 + heat6. Na (metal) + H2OCh100: Fundamentals for Chemistry 6Instructor: Tony Zable Name:_________________________To be performed by the instructor:5. Inspect some iodine
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