Video of group observing the texture of white powders shows a group observing the grain size of the powders by using their hands lenses and by pinching a small amount in their fingers. Each of these powders can be superficially described as a dry white powder, but they have different chemical and physical properties. The mystery powders in this activity have different physical properties, even though they are all white. Instead, use the wafting technique shown by the teacher. The objective of this study was to compare the physicochemical properties of egg white powder from eggs of different types of bird local kampung chicken, local fighting chicken, local serama. To identify an unknown white powder from a list of five substances by observing physical and chemical properties and changes in those properties. Students observe physical and chemical properties of white powders and then use those initial observations to help them. In previous labs, youve seen that many physical properties can be used to distinguish one material from another think about density and your first week of lab and even separate materials from one another think about properties like size, color, magnetism, and other. Vinegar, iodine solution, water, and radish or an indicator using a reaction cell plate or an index card, place a small amount of the solid powder into a reaction well, then add a few drops of the test reagents to each of the 5 powders. A simple definition ofpowder flowability is the ability of a powder to flow. Fifth grade lesson using properties to identify white powders. White powders a lab on standardized tests used to identify. New laser technology can identify unknown white powders. Physical changes can be tearing, grinding, melting, boiling, dissolving or any change that does not change the chemical identity of the.
These three powders baking soda, baking powder and cornstarch are nearly impossible to identify by sight alone so we relied on chemical and physical property changes when the various substances were mixed with three liquids. When vinegar was added to the powders, powder a formed a pasty homogeneous mixture once more. Make observations of the powders reaction with different solutions. Colemans approval on prelab questions before beginning the lab. Chemistry is the study of matter and the changes that occur to matter.
Baking soda, sugar, flour, cream of tartar, and chalk. New laser technology can identify unknown white powders from safe distance 8 october 2018 credit. When equal masses of na 2 co 3 and cucl 2 are reacted, a solid precipitate of cuco 3 is formed. After completing these qualitative tests, each group will receive an unknown corresponding to one of these white powders. To do this you must first carry out a series of tests on the white powders with known identities that are provided to. The video of students testing water reaction with white powders shows students adding a few drops of water to each pile of powders and discussing their observations. The unknown white powders are waiting for you in the lab. You will run tests on each of the white powders and record your results. You will then analyze a white powder collected from a locker at your high. Take on the role of a forensic chemist to identify unknown substances. A forensic scientist may discover powder at a crime scene. White powders lab 2014 hamilton township high school. The results of the research on the known powders can then be used to analyze several unknowns using the scientific method.
White powders a lab on standardized tests used to identify unknown substances objectives you will perform a series of tests to determine the physical and chemical characteristics of several unknown powders. Cc0 public domain white powders found at known or potential crime. A white powder is found spilled on the kitchen floor of a crime scene. Pdf physicochemical properties of egg white powder from. In your own words, what is your goal in todays lab. You will perform a battery of test on various known samples to determine the chemical and physical properties of those substances. Compare the data with results you collected as you performed various test on the 6 white powders. The unknown mixture will contain two or three white powders or clear liquids that the students. You are then expected to run the sample through all of the testing that you performed on the 6 powders. Analysis of a mystery powder as part of the investigation of a crime scene, detectives note that a white powder is found at the location. You are to use simple tests to find out what each powder is.
The white powders library consists of spectra of commonly found white powders. Powder b only slightly dissolved after some time had passed, and powder c fizzed once again, meaning that it reacted to the alkalinity of the water. You have 10 numbered samples of unidentified white powders, listed below. The library includes 165 spectra of commercially available white powders e. Prior knowledge questions do these before using the gizmo.
There are many types of reactions that occur in chemistry, and the one we are studying in this lab is a double displacement reaction. The binary 2component mixtures will be subjected to a battery of similar qualitative tests, and the observed data. White powders library listing 165 spectra this library is particularly useful to homeland security and national guard investigators. White substance analysis and identification lab target audience 912 background and notes. Background information jackson high school has a drug problem. Qualitative and quantitative analysis of white powders and. As part of your report, construct a table as shown below. Use their observations to determine the composition of a mixture of 2 unknown white powders. In order to determine if it is illegal or not the crime lab will identify the substance using chemistry. Differentiating white powders exploration lab dest917. As with the prelab table, write na in the box if the test was not performed. A temporary lab facility has been prepared at the high school. The unknown white powders are delivered to you in the lab so you can determine their identity.
Even though they have their suspicions, chemical and physical analyses must. Perform multiple experiments using several common powders such as corn starch, baking powder, baking soda, salt, and gelatin. Although each white mystery powder looks like the other. Remember a physical change involves a change in a physical property but the. In the exploration minilab today in class, our objective was to be able to distinguish three seemingly identical white powders.
You will need to develop your own procedure for this lab by reading the material given in this hand out. Complete the enlarged mystery powders lab paper to compile what each of the groups found. You have also learned some clues that tell you whether a physical change or a chemical change is occurring. To identify an unknown white powder from a list of five substances by observing physical and.
Lab report 02 five white powders scientific observations. How many of the white powders will be present in the unknown mixture you are trying to identify. Visitors will do a series of simple chemical tests with three white powders. By performing various tests, they are able to identify whether their powder is baking soda, baking powder, citric acid, corn starch, or detergent.
Biuret solution, iodine solution, litmus paper, vinegar. You will observe their chemical and physical properties to identify them. Revisit the idea of identifying substances based on their chemical properties. You will utilize your test results to identify an unknown substance. You have learned how to describe matter based on its physical and chemical properties. After completing these qualitative tests, each group will receive an unknown containing only two of these white powders. The purpose of this lab is to learn to identify the properties of starch, sugar, baking soda, and salt. Take one cup with white powder about 1 tablespoon and a stir stick. Can chemical reactions be used to identify an unknown substance. Once you have completed the analysis of the 6 powders, you will be given a sample of the powder from the vial in the victims home.
Mystery powders operating guide unit 7 crime scene chemistry u7. Read the entire lab and answer the questions that follow. Students will conduct a variety of chemical qualitative and quantitative analysis tests to gather data about a variety of known white powders and clear. Analysis of white powder lab by ashley obrey on prezi. You will perform a series of tests to determine the physical and chemical characteristics of several unknown powders. By this definition, flowability is sometimes thought of as a onedimensional characteristic of a powder, whereby powders can be ranked on a sliding scale from freeflowing to nonflowing. Activity 4 identification of white powders chem words ionic compound. Identifying the mystery powders using chemical or physical properties.
Mystery white powder experiment forensic science using chemical change to identify an unknown substance phenomena occurrence or event students investigate. The goal of this lab is to identify all five of the unknown white powders you are given. In this laboratory you will create a qualitative analysis scheme. The unknowns can be a single powder or a combination of the known powders. A similar powder is found on the shoes of a suspect in the crime. In this lab, you will play detective and use your chemistry knowledge to try to solve a crime. Physical and chemical changes background information. Unknown powders cornell center for materials research. Prepare unknown powder mixtures before the second part of the experiment. Students will create a professional lab report, journal article, or. Later you will compare these results with those from the tests run on the unknown powders collected during the locker seizures. Extend 10 minutes identify a substance based on a chemical property 17.
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