1. (4 points) The results below were obtained from a use-dilution test of two disinfectants. Cultures were inoculated into tubes with varying concentrations of disinfectants and incubated for 24 hr at 20°C, then subculture in nutrient media without disinfectants. (+ = growth; - = no growth) Disinfectant 1 Disinfectant 2 Concentration Initial Subculture Initial Subculture…
Question: Which salt type can melt ice at a quicker rate, Magnesium Chloride (MgCl₂) or Sodium Chloride (NaCl)? Background: The different states of matter are solids, liquids, and gases. Solids have a definite shape and volume, and have very little energy because the molecules in a solid are in a fixed position. Liquids have a definite volume, and have the second most/least amount of energy between the three states because its molecules move freely but closely together.…
Prior studies that have examined the independent effects of salinity and temperature on Daphnia have revealed that physiological rate processes including reproduction is negatively affected by increasing salinity, but the reproduction was positively affected by increasing temperature (Arner & Koivisto, 1993; Ghazy et al., 2009; Heugens et al., 2006; Schuytema, Nebeker, & Stutzman, 1997).…
Purpose: The purpose of this experiment was to determine the percent of chlorine in an unknown soluble salt through using gravimetric techniques. The unknown salt was dissolved in water and the chloride ions were precipitated using silver nitrate which produced silver chloride. The silver chloride was then separated by filtration techniques and through this the amount of chlorine in the original salt was able to be calculated. It is expected that the chlorine percent will be around 55.95% because that is the accepted value of chlorine content in the unknown salt.…
The results of the experiment clearly show that ultraviolet light has a lethal effect on Serratia marcescens, but only when having a direct access to the broth culture of Serratia marcescens. UV as a means of disinfection, in a hospital room or operating room, will be limited to surface contaminations or airborne contaminations. This is due to its inability to penetrate through surfaces and have direct contact with the microbial populations. Even though UV light has a reflective component it still will not have the capability to reach all surfaces. It will effectively eliminate this limitation in this environment is serious as bacteria can be in many places in which the UV rays will not have access, and thereby allowing these microbes the ability…
Introduction How does temperature affect the time glow sticks stay lit? Glow sticks are fun, safe, and interesting to kids all around the year. These light sticks were made for military purposes which were patented in 1973, but Edwin Chandross of Bell Labs’ oxalyl chloride and hydrogen peroxide glow stick was patented in 1960’s. Chemiluminescence is a luminescence resulting from a chemical reaction which is how glow sticks work.…
Although many citizens may believe otherwise, it has been proven that the uses of police body cameras are beneficial to all aspects of law enforcement. In the article, “Scholar Warns Body Cams Used to Show Underrepresented in Worst Light,” freelance journalist and well renowned writer Jamaal Abdul-Alim argues that the use of police body cameras will result in the reduction of both complaints against officers and police force. Abdul-Alim supports his main argument when he presents a yearlong study on the effect police body cameras have on law enforcement that states, “Wearing BWC’s by police can reduce both officer use of force and subsequent complaints against officers” (8). Abdul-Alim then goes into the specifics when he provides the reader…
Prompt 2. The purpose of this paper is to discuss the lightness constancy and how it works. Including how the visual system works with constancies, to properly attribute uniform color to a surface. The way to go about the task is with an example.…
Isopods are interesting creatures that have been decided to experiment upon as the test subjects. However, the term isopods, generally refers to the order Isopda but to be more specific pill bugs are a subcaterogy. Therefore, the classifacation for them are the family Armadillidiidae, which means that they have the ability to conglobate/curl into a ball, acting as a defense mechanism for them if and when they are in danger. Additionally, the best known and most investigated is Armadillidium vulgare, also known as the common pill bug. The experiment is being conducted to see whether they prefer to be in a wet or dry enviroment, in other words, their response to moisture.…
Osmosis is the net movement of water towards higher concentration. In osmosis experiment, water likes to diffuse from an area of low-solute concentration to an area of high-solute concentration. The purpose of the osmosis experiment was to observe the diffusion of solutes and the osmosis of water through a semipermeable membrane, which was dialysis tubing. This experiment was done to examine, if the solution is hypertonic, hypotonic or isotonic.…
Verlyn Klinkenborg, author of “Our Vanishing Night”, explains exactly why light pollution has spread. "We are diurnal creatures, with eyes adapted to living in the sun's light” (Klinkenborg pg.478). He explains that humans have filled the night with light, so we have an easier time adapting to the darkness. However, with this comes consequences with our actions. Klinkenborg is effective when persuading the audience that light pollution is a problem.…
its color led to the formulation of this experiment. The experiment utilizes chloroplasts of spinach leaves to test the different color lights’ effects on photosynthesis. Green light is said to be the least effective at driving photosynthesis on the electromagnetic spectrum due to being mostly reflected and transmitted instead of being absorbed. Conversely, red light and white light is more effective at driving photosynthesis (Reece, 2011). Thus, a hypothesis was created stating that the rate of photosynthesis will be greater with a red light bulb compared to a green or white fluorescent light bulb.…
The purpose of the Light, Color, and Solutions experiment was to determine how to use a spectrophotometer, understand the relationship between a solution’s visible color and its color absorption, and to derive, understand, and use Beer’s Law. Some background information that would be helpful included that the color of a solution was determined both by the colors it absorbed as well as the colors it transmitted. For example, if a solution was viewed as the color red, then red light was transmitted by the solution while the complementary color, green, was absorbed. Beer’s Law stated that the amount of light that passed through a sample was limited by the light’s wavelength,…
Kaitlyn Staub Mr. G Biology Honors 4 January 2016 Title The Effect of Different Music Genres on the Growth of the Bacteria Serratia marcescens Introduction Exploring the question of does music affect bacterial growth requires much research. The purpose of answering this question is to figure out how to slow down bacterial growth by music.…
During the entire lab, the main purpose was to, Identify the given unknown salt through a variety of experiments which yielded valuable quantitative and qualitative data. Before any experiments were carried out, multiple properties were compiled in order to have a source to compare the found results with. Beginning with the first experiment to determine if the unknown salt was hygroscopic, efflorescent, deliquescent or none of the above properties. This test was done through weighing an amount of the salt and reweighing after 15 minutes which would show if the salt had one of the above properties (either by gaining mass from the air, losing mass to the air, turning to solution) or none of the properties. Furthermore, tests were done to identify…