Claim: Through the tests performed in lab, it was concluded that unknown powder E was NaHCO₃, powder K was MgSO₄ and powder V was cornstarch. Evidence: Unknown element E was first tested with phenolphthalein and the solution turned pink, this test left 3 possible compounds; NaHCO₃, Na₂CO₃, and CaCO₃. Next the compound was tested with iodine and the solution turned yellow showing that now there was two compounds that could be the identity of unknown powder E; NaHCO₃ and CaCO₃. After that compound E was tested for being soluble in water, the powder was soluble, this proved that unknown element E is NaHCO₃. Unknown Element K was also first tested following the steps for the phenolphthalein test and the compound turned clear, this test ruled out NaHCO₃, Na₂CO₃, and CaCO₃. Second the unknown powder was tested with iodine and the solution turned yellow, leaving NaCl, CaSO₄ and MgSO₄ as possible identities of unknown powder K. Considering this it was next tested for solubility in H₂O, and it was concluded that the compound was soluble. Next the unknown element was tested with sodium hydroxide and a white precipitate formed proving that unknown powder K was MgSO₄ because NaCl and CaSO₄ were ruled out. The last powder tested was unknown element V. Like the other powders …show more content…
Second unknown element V was tested with iodine and the solution turned a deep
Discussion 1. Zn0 (s)+ Cu2+S6+O42-(aq) →Cu0(s) + Zn2+S6+O42-(aq) Zn0(s) → Zn2+(aq) + 2e- Cu2+(aq) + 2e- → Cu0(s) Zn0(s) + Cu2+(aq) → Zn2+(aq) + Cu0(s) Oxidant (oxidizing agent) is the element which reduces in experiment.
Identification of bacteria within Unknown Culture #21 In this experiment, an unknown culture of two different types of bacteria was assigned to each person, a number of tests were performed to isolate and identify these bacterial cells. Based on knowledge from the previous experiments completed in lab, a basic understanding of each type of bacteria was used to create a flow chart that would aid the process of identifying the unknown bacteria within the culture. A gram stain that is performed initially will narrow down the types of tests certain bacteria will and will not respond to. In addition to the gram stain, some of the tests that were used include, a catalase test, an Eosin methylene blue (EMB) agar test, a bile esculin test, and a 6.5% sodium chloride (NaCl) test.
All matter is made of particles called atoms. An atom is smallest unit of matter. A matter can be solid, liquid or gas. When a group of atoms bond together this makes a molecule. The molecule is the base of chemical compounds that is involved in chemical reactions.
According to the observations recorded, the metal ion Cesium is present in the “unknown samples”. Unknown sample number five produced a violet color when placed in the flame. Unknown sample number four produced an orange color when placed in the flame. Unknown sample number one produced a violet color when placed in the flame. This evidence supports the claim that the metal ion Cesium is present in the unknown samples according to table two, the Flame Spectra of the Alkali and Alkaline-Earth Elements.
Physically, the unknown compound was composed of white, grainy, crystal-like structures. The unknown was also odorless. From these observations, various physical and chemical testing was performed to determine properties of the unidentified compound. A series of solubility tests were performed, as shown in Table 2, and revealed that the unknown compound was soluble in water, but not in Acetone or Toluene.
Determining the Identity of an Unknown White Compound Maxwell Yurs Group Member: E.B. Floersch, Alexander Medina, and Masih Horri College Science and Engineering University of Minnesota, Minneapolis October 12, 2014 The experiments that were completed were used to determine the identity of an unknown white compound to allow for proper disposal. These experiments included flame tests, pH tests, and conductivity tests. After each was completed, it was found that the identity of the white compound was Sodium Nitrate.
As seen in table 1, the theoretical yield was .712 g of C_17 H_19 NO_3. The % yield of this experiment was 7.51 % of C_17 H_19 NO_3. . This low yield can be explained from a poor recrystallization technique combined with potential contamination. Throughout the experiment, the mixture changed color from green, orange, to yellowish lime, and eventually clear.
We identified unknown A as acetaminophen. This is because unknown A had all the same tested properties as acetaminophen when we performed our tests. For unknown B we found it to be acetaminophen and caffeine. This is because like unknown A, unknown B properties were the same as acetaminophen, but unknown B was acetone soluble. Unknown B has similar properties to caffeine because it was acetone soluble and because caffeine was the only basic pH tested to change color during the FeCl3 test.
Abstract: The purpose of this experiment was to identify given Unknown White Compound by conducting various test and learning how to use lab techniques. Tests that are used during this experiment were a flame test, ion test, pH test, and conductivity test. The results drawn from these tests confirmed the identity of the Unknown White Compound to be sodium acetate (NaC2H3O2) because there were no presence of ions and sodium has a strong persistent orange color. The compound then will be synthesized with the compounds Na2CO3 and HC2H3O2 to find percent yield.
Exercise 14: Unknown Identification Lab Report The purpose of the study was to identify the unknown bacterium using various biochemical tests in addition to using scientific methods in determining the outcome of the hypothesis. Each biochemical test will help determine the bacteria based on specific characteristics of each organism. I was giving unknown number 232. The first procedure that needed to be done after obtaining unknown bacterial mixture was to isolate the two bacteria in a pure culture using the streak plate method described in Microbiology Laboratory Manual Eight Edition. The material used was trypticase soy agar (TSA) plate, nutrient plate, starch agar, hydrogen peroxide, iodine reagent and microscope.
Experiment 2 Report Scaffold (Substitution Reactions, Purification, and Identification) Purpose/Introduction 1. A Sn2 reaction was conducted; this involved benzyl bromide, sodium hydroxide, an unknown compound and ethanol through reflux technique, mel-temp recordings, recrystallization, and analysis of TLC plates. 2. There was one unknown compound in the reaction that was later discovered after a series of techniques described above.
Name : Terry-Ann Poorman Id # : 27120454 Lab# : 1 Lab Instructor: Mrs. Bryan Title : Aim : Discussion Questions: 1) What are the types of urine specimens? Random specimen This type of specimen is used for microscopic and chemical analysis. As the name suggest this sample can be a randomly collected specimen and at an unspecified times.
Selenium - The Element In 1817, Jöns Jacob Berzelius found out an unknown substance with properties similar to that of tellurium and named it as Selenium, from the Greek word Selene, which denotes goddess of the moon1. Selenium is one of the rarest elements that are found naturally in the earth’s crust. It occupies group 16 (chalcogens) of the periodic table of elements with atomic number 34 and symbol Se. Selenium exists in multiple allotropic forms but only three are recognised. The most stable form is a metallic gray crystalline hexagonal selenium, second is crystalline monoclinic selenium which is deep red in colour and the third one is amorphous selenium, which appear red in powder form and black in vitreous form.
Potassium Chloride Lab Report - Seya Introduction The reason why we chose to test the solubility of 50ml of water at various temperatures is because KCL is known to have constant data and therefore leads to better results. The solubility of potassium chloride in water is due to ion-dipole interactions. Research Question Time needed for (2g) Potassium Chloride to fully dissolve compared to the temperature (20°C - 70°C) of the (50ml) Water.