Our objective was to pick the best chemical to be used in a hand warm. This chemical had to be cheap, relatively safe, and must raise the temperature by 20oC and no more. We add 6 different chemicals to water we record the inshell temperature and then add one a the 6 chemicals to the water and record the temperature change of the water. We also add cold water hot water together to find how much heat would escape the calorimeter. We found that the calorimeter absorbed 71.1J/oC. Then this information to calculate the energy that was released by all of the chemical reaction.
The absorbance and the maximum wavelength of all eight standard solutions were determined using the same spectrophotometer in this section. First, approximately 3 mL of each solution was added into a cuvette using a plastic pipette. The solution was added until the level reached the frosty part of the cuvette and any bubbles were dislodged by gently tapping the cuvette against a hard surface. Then, a Kimwipe was used to clean the exterior of the cuvette. Once cleaned, the cuvette was transported by only holding the top edges.
The lab started off by measuring critical materials for the lab: the mass of an an empty 100 mL beaker, mass of beaker and copper chloride together(52.30 g), and the mass of three iron nails(2.73 g). The goal of this experiment is to determine the number of moles of copper and iron that would be produced in the reaction of iron and copper(II) chloride, the ratio of moles of iron to moles of copper, and the percent yield of copper produced. 2.00 grams of copper(II) chloride was added in the beaker to mix with 15 mL of distilled water. Then, three dry nails are placed in the copper(II) chloride solution for approximately 25 minutes. The three nails have to be scraped clean by sandpaper to make the surface of the nail shiny; if the nails are not clean, then some unknown substances might accidentally mix into the reaction and cause variations of the result.
We are doing a gummy bear lab. Gummy bears come in different sizes, shapes, and colors. Gummy bears are squishy, chewy, and sticky, they are made of sugar which are glucose and glucose are carbohydrate. We predict that during this stage of lab the solute and solvent will go through the stages of hypertonic, hypotonic and isotonic. We get 4 gummy bears and 4 cups filled half way with different types of liquid, such as Salt-Water, Coffee-Creamer, Vinegar, and Soda.
In the “Blast Off” lab, we had launched a foam rocket into the air by pumping air into a nozzle, shooting the rocket up, and then recording the time from launch to when it hit the ground. I have learned and now understand the mechanics of kinetic and potential energy. The experiment I had conducted relates to energy in that as we observed the rocket, its energy was constantly transforming as it was in motion. Kinetic energy is an object’s energy based on its motion. Potential energy is energy based on an object’s shape or position.
Unknown Lab Report Abiola Oyewumi March 16, 2015 Unknown #16 Abstract An experiment was conducted to determine which of the following unknown bacteria was in test tube number 16: Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, and Salmonella typhimurium. Biochemical tests were used to help identify the unknown bacteria. The Citrate test, Urease test, Triple Sugar Iron Agar test, Voges-Proskauer test, and Methyl Red test were the biochemical tests used in this experiment.
Group 1: All the elements that were tested from group 1 had a pH level of 12. This meant that all the tested elements produce an alkaline solution. Group one elements readily lose their valence electron as they wish to form a full valence shell this gives them all a low electron affinity. The group one elements have different electronegativity going down the group. Electronegativity of the elements decreases with the increasing the atomic radii.
ST Report In the experiment, the problem was the contaminants that were affecting the quality of the water samples. To fix this issue, three scientists had to determine the contaminants that were present in the samples. One sample was from the school sink and the second sample was from an unknown source. The scientists conducted many tests to figure out what pollutants were present in the water.
Leah Romero 10/30/2017 Conclusion Lab 3 Chem 102L In lab 3, fundamentals of chromatography, the purpose was to examine how components of mixtures can be separated by taking advantage of different in physical properties. A huge process in this lab was paper chromatography, which was used to isolate food dyes that are found in different drink mixes. The different chromatograms of FD&C dyes were compared to identify which dyes are present in each of the mixes.
The solution with pH 3 has a higher H+ concentration than the one with pH 12. The numbers 12 and 3 signify whether a solution is acidic, neutral, or basic (alkaline) based on the concentration of hydrogen ions contained within the solution. If an anthocyanin molecule is added to a solution and releases a proton once being added into the solution, the anthocyanin molecule is behaving like an acid. A proton (or a hydrogen ion), is being lost, which is a characteristic of an acid. When anthocyanin molecule is being added into a solution, the double bonds shift and its color changes depending on whether the solution is acidic or basic.
Variables Independent variable – the variable which will be manipulated throughout the investigation is the primary protein structure of the genes that will be compared across the organisms. The primary protein structures of genes which will be compared are insulin (INS), retinal (RPE65), growth hormone (GH1), amylase (AMY1A), and pepsin (PGA5). The entire sequence of the protein of the selected genes will be compared for all the organisms. Dependent variable – the variable that is affected by the independent variable.
At the macroscopic level when a firework goes off the effects of molecules interacting can be observed through the light being produced. I expect the firework to travel to a high distance vertically in the air. I expect the firework to start in a tight ball. As it travels the tight ball (of molecules) will expand in its perimeter causing the firework to combust, making a very loud bang. I’m sure that heat radiates as a outcome of this interaction, though it wouldn’t be smart to get close enough to feel the heat.
Determining the percentage of sodium carbonate in a sample of washing soda crystals Aim The purpose of the experiment carried out was to determine the percentage of sodium carbonate (Na2CO3) in a known amount of washing soda crystal, using the titration technique. Acids & Bases Water is the most common acid and base found on earth. An acid is anything that can donate a proton/H+ and a base is anything that can accept a proton/H+ – Bronsted-Lowry. Water being able to both accept and donate a proton/H+ is both an acid and base.
Properties of Substances Express Lab 1)The purpose of this lab was to compare the physical properties of different types of solids and how the properties of solids are determined by their intermolecular forces and their intramolecular bonds. Then we were to classify each type of solid as either ionic, metallic, non-polar molecular, polar molecular, or network. Paraffin wax classified as a non-polar molecular, Silicon dioxide was classifies as a network, Sodium chloride was classified as ionic, Sucrose was classified as polar molecular and Tin was classified as metallic. (2)The intermolecular forces that are present in Paraffin wax are dispersion forces, because it is non-polar and carries a negative charge. Followed by Sucrose that has
Joshua Miller 12/18/17 Fermentation Lab report Introduction The term fermentation refers to the chemical breakdown of a substance by bacteria, yeasts, or other microorganisms, typically involving effervescence and the giving off of heat (wikipedia). Sugars are converted to ethyl alcohol when fermentation happens. In this experiment we determined if yeast cells undergo fermentation when placed in a closed flask with no oxygen. Glucose and yeast are mixed together in a closed flask and allowed to incubate for about one hour.
