The purpose for this procedure is for students to familiarize themselves with how different types of properties can lead up to identifying substances. For the safety of this experiment be sure to always have your goggles on and tightly secured, due to any splattering of chemicals or glass breakage. Under no circumstance should any chemical be near your mouth. In this procedure students will use four methods that will help identify what is their unknown substance. Once all methods are done its data will provide physical properties of numerical values which students will compare to the list that will lead to identifying their pure substance. The four methods in this experiment are finding the density (g/mL), the solubility, the melting point …show more content…
The laboratory tools used in this part are three dry test tubes and a cork. The second method is density; however, it will depend what state your unknown is, for solid students will follow choice A and if the unknown is liquid its choice B. For finding the density of a solid students will be using volume displacement. In this case the only tool will be a 25-mL graduate cylinder. For finding the density of a liquid, students will use a dry conical flask, stopper, test tubes, a pipet, and a balance. Students will weigh first to find their initial reading then with a pipet transport the liquid to the flask. Remember the volume of the pipet will also be used to finding the density. The flask will be then weighted again to find the mass. It is good to remember to always handle all glass with caution to prevent any breakage. The melting point method is only for those that have a solid unknown. Since this part requires using a Bunsen burner all long hair should be tied up for safety precaution. A 250-mL beaker, capillary tube, thermometer, a ring-stand and a rubber band will be used for finding the melting point of a
Experimental Summary: First, my partner and I put the marshmallow and cheese puff on T-pins and used the Electronic Balance to measure the mass of each of them. Next, we put 100 mL of water in the 100 mL Graduated Cylinder and poured it into the 12 oz. soda can. We measured the temperature of the water with the thermometer. After
Introduction: Someone in a restaurant has suddenly fallen ill and a mystery powder has been discovered with the victim. As the chief investigator, your duty is to identify the mystery substance through a lab. In this lab, it will consist of five known compounds and one unknown compound. Your job is to distinguish which one out of the five substances is the mystery powder. To figure out the mystery matter you will have to compare their physical and chemical properties and match them with the appropriate compound. Furthermore, you will compare their reactions with water, universal indicator, vinegar and iodine solution to discover what the mystery powder is.
... dichloroethane the density was 1.24 (1,3) making it most likely the unknown. Another property was the boiling point. The boiling point of the unknown during the experiment was 86.6 ℃; in comparison 1,2- dichloroethane was ±0.03℃ within the range, 83.3 ℃ (1,3). Lastly, to top it all the IR spectrum was closely related to the IR of the unknown. Researching the identity I also found a physical description of 1,2- dichloroethane that matched my description of the unknown, “Colorless liquid with a pleasant, chloroform-like odor” (1). I learned in the experiment that the numbers from my results for the unknown does not have to be exact for it to be identified. As long it is in a certain range the unknown should be known by using research and background knowledge. I also learned that there are many factors that can affect an experiment whether it is systematic or random.
The melting point of the unknown was determined for both pure (recrystallized) and impure (original) powders. To perform thee melting point procedure the powders were placed in small tubule. The tubule was placed in a Mel-temp device and the melting range was recorded. The data is present in the form of a range in the following chart:
Journal: when i was doing my experiment the first thing i had to do was get my materials that are 1) clear drinking glass 2)¼ cup of vegetable oil
To properly complete this lab, a basic understanding of mass, moles, and empirical formula is required. Mass is a unit of measurement that is used to determine the number of grams in a certain object. A mole is a measurement in which the amount of substance that is present can be determined.To convert between from mass to moles the amount of grams present is divided by the atomic mass to find moles. To get back to mass from mols the amount of mols is multiplied by the atomic mass. An empirical formula is a chemical equation with the simpliest positive ratio possible. To find an empirical formula the elements in the formula must be in moles. Then the smallest amount of moles is used to divide all the other mole numbers. These numbers
The compound that was assigned to be tested and the identity to be discovered was blue in color. Once 0.5028 grams of the blue compound was weighed out it was combined with 5 mL of distilled water. initially the unknown compound didn’t seem to dissolve in water. However, after a few minutes of constant stirring the substance dissolved completely. Thus indicating that the cation in the unknown compound was Cu2+. The identity of the cation had to be confirmed therefore a flame test had to be preformed. Once the solution was placed over the Bunsen burner the flame turned green confirming that the cation was Cu2+. To determine the character of the anion 0.1087 grams of the unknown compound, and 0.5109 grams of Na2CO3 was measured. Both solids were
To be able to identify what kind of macromolecules a solution has, it has to be tested to be able to identify what macromolecules are present in the solution. Here we used only one test for each macromolecule that we are testing for. We tested for RNA, DNA, protein, sugar, starch, and lipid macromolecules. Using these kinds of test we were able to figure out, that we can detect what kind of macromolecules are present in a solution almost with full accuracy.
In this lab experiment, around 5 grams of hydrogen peroxide went through a chemical reaction with potassium iodide, producing oxygen gas and water vapor. After three trials of the experiment concluded, Dalton’s law of partial pressure and the ideal gas law was used to determine the number of moles of oxygen produced and the percent hydrogen peroxide in an aqueous solution. The average number of moles of oxygen produced within the experiment was 0.002537 mol. O2 and the average mass percent of hydrogen peroxide was calculated as 3.434%. The mass percent of hydrogen peroxide was slightly over the accepted amount of 3%, indicating that some tiny errors had occurred during the experiment.
Biochemists want to know as much as possible about the effects and enzyme has on overall reaction rate. Plenty can be established about how an enzyme works simply by measuring how quickly it catalyzes a reaction under a series of different conditions.
In today's medicine, correctly and quickly identifying a patient's illness is essential for proper treatment. In order to execute this, biochemical tests of various magnitudes are used to identify what a patient may be infected with. In our lab, we received an unknown sample of urine. After several biochemical tests, we determined our unknown specimen to be Enterobacter aerogenes.
Medical diagnosis and lab testing can becommercial uses for biochemical testing to diagnose diseases. Animals are also checked for diseases and to make sure they are acceptable for human ingestion.
This is the amount formed at time t=50 - the amount formed at time t=40 divided by 10 seconds.
Procedure: The student will read the IR spectroscopy of the unknown first. Then perform various tests and measure the boiling point.
It is important in biology to understand how species traits determine their “demographic performance” in an ecosystem (Iida et al., 2014). Trees are vital to the environment as they are able to take in carbon dioxide that is excreted from non-photosynthetic organisms and replace it with oxygen. Previous studies have found that the growth rate of trees is the main trait responsible for the mortality and prosperity of that species of tree (Iida et al., 2014, Kohyama et al. 2003). However, to properly understand growth rate of trees and the causations, it is vital to understand the shoot growth of tree branches. The growth of a tree occurs within its branches which happens cyclically. The terminal bud develops at the end of the