Reservoir Water Lab Report

Purpose: The purpose of this lab is to familiarize you with osmosis and, specifically, what happens to cells when they are exposed to solutions of differing tonicities.

3. Put one wet circle into each petri dish and create raised ridges in the paper towel, creating a valley for each of the five seeds.

The experiment had two part, each part consisted of two trails and each two team members did one trail simultaneously. The goals of the first procedure was to confirm the mass of water % in a known hydrate, CuSO4 *5H2O, then to conform the empirical formula of the hydrate. Part two was the same procedure as part one. However, instead of a known hydrate, an unknown hydrate was given.

This method also helped with food production of the plants. The corn would provide the shade and climbing structure for the beans which allowed the plants to flourish. The squash was planted between the rows of corn and was ready soon after the corn was harvested.

"PH is the measure of h+ (hydrogen ions) and translates as the power of hydrogen" The term ph indicates the measure of hydrogen ions in a solution. The pH scale is a logarithmic scale that represents the acidity or alkalinity/basicity of a substance. As seen in figure 1 the Ph scale runs from 0.0 to 14.0 with 7.0 indicating neutral. Image (Anon 2017)

Using the collected data, the rate of water loss from the sand needs to be calculated using the psychrometric chart and the change in weight of the sand mixture over time. To illustrate the process of calculating the water loss, the equilibrium data from Trial 1 will be used. T_(wb,out)=24.5⁰C T_(db,out)=50.5⁰C T_(wb,in)=23.5⁰C T_(db,in)=50.5⁰C With the wet and dry bulb temperatures, the psychrometric chart was used to find the moisture contents and humid volumes for the air at the inlet and outlet of the tray dryer. The values found using the psychrometric chart are provided below. H_out=0.93 m^3/(kg dry air ) H_in=0.93 m^3/(kg dry air )

I. Introduction: • The cell is the smallest basic element of all life, but it has incredible biological organization functions such as metabolism, growth, movement, reproduction, and heredity. A human cell has three major parts: the plasma membrane, the cytoplasm, and the nucleus. The plasma membrane is a partially permeable membrane which controls substances entering or leaving the cell. It also acts like a barrier blocking harmful things from entering the cell and lets nutrients in. There are two types of movement across the plasma membrane: passively or actively.

Measure and record the height of each plant everyday for 2 weeks. For each day, calculate the growth of each plant by subtracting the measurement at day 0 from the measurement at that day.

osmosis diffusion of water across a selectively permeable membrane depending on the concentration of solutes on either side of the membrane isotonic solution in cells, a solution in which the concentration of dissolved substances in the solution is the same as the concentration of dissolved substances inside a cell hypertonic solution in cells, a solution in which the concentration of dissolved substances outside the cell is higher than the concentration inside the cell; causes a cell to shrink as water leaves the cell hypotonic solution in cells, a solution in which the concentration of dissolved substances is lower in the solution outside the cell than the concentration inside the cell; causes the cell to swell and possibly burst as water

Water is a chemical substance of which is scientifically called H2o. This means that each of the molecules contains one oxygen and two hydrogens. In the experiment the water was solidified into ice cubes and therefore the experiment was a physical change, due to the substance not changing when the ice melted. There were no chemicals added into the experiment therefore it was not a chemical change the water molecules were still water molecules. When heat is added to a substance the molecules vibrate faster, and as they move faster the space between the molecules increases, eventually causing the substance to turn into a gas if heated long enough.

In this experiment, I attempted to demonstrate the natural process of osmosis in life. To do so, five bags with semi permeable membranes containing different concentrations of sucrose or water were soaked in water or sucrose and their weight was measured at different time intervals. To minimize errors, I calculated the averages for each bag at each time interval for all the groups and observed that Bags 2, 3, and 4 which contained various concentrations of sucrose had a significant average net weight increase over time. While bag 5 that contained tap water and was soaked in a high concentration of sucrose, showed a substantial average net weight decrease. Both of these findings are due to the movement of water molecules across the semi permeable

Discussion Hypothesis 1: Experiment 1, I accepted my oil hypothesis because the oil formed a thin even layer on top of the water and resumed after I stirred it up with the wooden stick. Vinegar hypothesis: I accepted because the vinegar was only identifiable by smell. Laundry detergent hypothesis: I accepted because the laundry detergent contaminated the water by changing the color to greenish blue and formed bubbles. They all had an effect on either the smell or consistency of the water. The detergent seemed to be the most potent when it came to the water, only because it changed the smell, the color and the constancy of the water.

We did Lab 2 part 1, first we found the weight of the graduated cylinder and 10 ml of water. Then we found the weight of the graduated cylinder. After that we found the we found the weight of the 10 ml of water by subtracting the weight of the water and the cylinder by the weight of only the cylinder. We found the volume of the water by seeing how much the water rises but it did not rise from 10 ml mark because no object or weight was in the water. The density of the water is mass divided by volume. Our volume was 1 ml and our, mass was 9.8g, and after dividing those two numbers we got a density of .98g/ml. But the density of pure water is 1.0, and the density we got for the density of tap water which is not pure water, is supposed to weigh more than the pure water. In Lab 2 part 3 the wt of the 10 ml of salt water and G.C together was 37g about 1g difference from the weight of 10 ml of H2O and the G.C. The weight of the G.C alone is 27g. The weight of the salt water alone is 10g, the volume of it was 10ml. The density of the salt water was 1g/ml. The discrepancy in this data about part 1 and part 3 of lab 2.The data of the 2 parts only have a difference of 1g or lower.

Next I had to set up my work space to provide myself with the most accurate results. I cleared off a window seal in my house that sets on the south side of my house where the sun would best hit the plant. I then cleared out a spot in my brothers closet for the second plant, which would work better than mine would have considering he never goes in his closet. Something else that probably wasn’t necessary but helped in the long run was I set out all of my equipment so it wouldn’t be such a hassle and I wouldn’t have to worry about not being able to find everything.

In this experiment you will be using different percentages of sucrose solutions and food coloring along with dialysis tubing to visibly and physically display osmosis. Osmosis is the diffusion of a solvent across a semipermeable membrane to reach an isotonic state (Fitzhugh 47). A solution becomes isotonic when there is an equal amount of solvent flowing evenly through a semipermeable membrane in and out of dialysis tubing. The purpose of this experiment is to better understand what happens during osmosis and to be able to recognize that it happened. I predicted that, if the percentage of sucrose was higher in the beaker than in its corresponding dialysis bag, then the weight of the dialysis bag would increase and vice versa.