Concentration Essays

Colligative Properties

Abstract: Several experiments were performed to observe the colligative properties. This includes the freezing point depression, and osmotic pressure. Two ice baths were made, one with pure water, the other with salt water. The lowest temperature was then record for each bath and compared. The salt water had a lower freezing point than the pure water by 2 degrees which supports the hypothesis that solutions have a lower freezing point than pure water. The second property observed was osmosis pressure….

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Fabtek (a) Case Analysis (harvard Business School 9 592 095)

Fabtek the first company to provide titanium products for industrial use had create a competitive advantage on the process of welding, heat treat and thermal cutting of this metal on the Philadelphia and US titanium business market. At this moment the company is working hard to rebuild a good image in the market after some customers dissatisfaction with late job deliveries. To resolve it is important to increase the communication and cooperation between the engineer department and manufacturing. Other issue…

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The Beer Lambert Law and Its Limitation

Objective : 1. To determine the linear relationship between absorbance and concentration of an absorbing species. 2. To study the effects of molecular dissociation complex formation on the applicability of the Beer-Lambert Law. 3. To investigate the derivation and limitation of Beer-Lambert Law. Introduction: In optics, the Beer–Lambert law, also known as Beer’s law, the Lambert–Beer law, or the Beer–Lambert–Bouguer law relates the absorption of light to the properties of the material through which the light is traveling. The general…

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Investigating the Difference in Isotonic Point in Sweet and White Potato

To observe whether equal sized white potato or sweet potato cores reached the isotonic point in the same concentration of sucrose solution. Introduction: Osmosis is diffusion of water from areas of high water potential to areas of low water potential. It does not require an input of energy. Plants use osmosis to transport minerals from their roots to their leaves, and to take in water in the soil. Because the plant cell is taking in water and minerals, its mass…

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Cell Transport Mechanisms and Permeability

Exercise1 Cell Transport Mechanisms and Permeability Name ____________________________________________________________ Lab Time/Date ______________________________ Activity 1 Simulating Dialysis (Simple Diffusion) 1. Describe two variables that affect the rate of diffusion. * The size of the pores of the membrane * The size of the molecule diffusing through the membrane 2. Why do you think the urea was not able to diffuse through the 20 MWCO membrane? How well did the results compare with your prediction? * Because the pores of the membrane were…

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Sedimentation_ Tangent and Concentration

Sedimentation is the process of separating a liquid mixture of suspended particles into clear supernatant liquid and denser slurry having a higher concentration of solids. This is usually accomplished by allowing the particles to settle through the force of gravity, mechanically using centrifugal force, or electrostatically using an electric current. Continuous sedimentation tanks are usually used in wastewater treatment facilities to separate suspended particles from wastewater. This experiment aims to determine the effect of initial concentration and initial height of…

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Experiment to Investigate Osmosis in Potatoes

The aim of this experiment is to investigate the movement of water in and out of plant cells. The cells chosen for study will be taken from potato tubers. Firstly I will explain what osmosis is. Osmosis is the passage of water from a region of high water concentration through a semi permeable membrane to a region of low water concentration. This definition contains three important statements: a) It is the passage of water through a semi permeable membrane b)…

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Nacl Solutions

The different concentrations of NaCl solutions led to the net movement of water molecules in the samples through osmosis. The samples soaked in higher NaCl concentrations, 0. 75 M and 1 M, slightly increased in mass due to less absorption of water. Samples soaked in less NaCl concentrations, on the other hand, became bulky due to considerably high absorption of water. As discussed by Bowen (2000), water molecules flow from the solution with low solute concentration to the part with…

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Water as a Universal Solvent

* Because of its high polarity, water is able to dissolve most substances. * In a solution, the positive hydrogen side of water is attracted to the negative parts if the compound it is dissolving while the negative oxygen is attracted to the positive parts * “Like dissolves like” – describes whether one substance will dissolve in another. Water for example can’t dissolve nonpolar substances Concentrations on Solutions * Solvent: The liquid in which a solute is dissolved to form…

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Geographies of Social Difference

Map 1: [Figure 2, People not fluent in English as a percentage of the total population aged 5 years and over, Sydney, 2006] (a) Compare the spatial pattern of the map to the map of unemployment. Does the map share the same spatial pattern as unemployment (i.e. do the areas of high and low concentration match)? Describe the similarities and differences in the spatial pattern. Figure (1) displays that there is a high prevalence of unemployed people in the Western…

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The Effects of Osmosis

Introduction: Osmosis is a movement of water across a semi-permeable membrane. This may only happen when there is a difference in concentration between the two sides of the membrane. The water moves from low concentrations to high concentrations. That is because the low concentrated area tries to dilute the opposite via osmosis. The effects osmosis has on a cell are either that it becomes turgid and hard as water enters the cell or it becomes dehydrated (this is called plasmolysing…

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Solution Preparation

1. Why should the solutions be prepared with 0.10M HCl used as solvent? a. What will happen to Fe3+ if the solution was not prepared using 0.10M HCl? b. Give the balanced equation for the 1st hydrolysis of Fe3+. c. What is the color of the product of 1st hydrolysis of Fe3+? d. What is the effect of the product of 1st hydrolysis to the absorbance of the solution? Determination of Analytical Wavelength 2. Why should the solution with highest…

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Determination of Copper by Complexation

ABSTRACT To determine the concentration of copper in an unknown solution by using copper complexation, solvent extraction and spectrophotometry. Standards are used to create a calibration curve and the unknown concentration of copper is then calculated by using the linear equation from the calibration curve. The concentration of copper in the unknown solution 201 was found to be 12.57± 0.25 μg/mL. INTRODUCTION Copper is an essential mineral in everyday life, it is in necessary for the production of red blood…

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Determining the Osmolarity of a Potato

Abstract Students in Biology find it difficult to understand the concept of tonicity and osmolarity in a real time situation. In this investigation, several concentrations of sucrose were used to determine the osmolarity of a potato. It was found that the concentration of sucrose was close to 3.6 in the potato used showing that it was isotonic. Anything above caused the potato to gain weight showing that it was a hypotonic solution and anything below caused the potato to lose…

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Why Doesn’t Jelly Set When Fresh Pineapple Is Used_

Basic Problem: Jelly is made from protein, gelatin, this is dissolved in hot water and as it cools, it sets. For a childrens party it was decided to make some fruit jellies, these were made by putting sliced pineapple into the jelly before it set, the following observations were made: oThe jelly set normally when tinned pineapple was added. oWhen fresh, unripe pineapple was used the jelly set but was not as firm. oWhen fresh, ripe pineapple was used, the…

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