Make sure to keep time, read the spectrometer, and record the data. Note time to the nearest second and mix the contents of tubes 2 and 3 by pouring them back and forth twice. Mixing should be completed within ten seconds. 5) Add the reaction mixture to a cuvette by pouring or using eye dropper, wipe the outside, and place the cuvette in the spectrometer. Read the absorbance at 20 second intervals from the start of the mixing.
Pre Lab Objective: The purpose of this lab is to obtain the mass and volume of two different metal samples, to graph data, to obtain the slope of graphed data and to display a best fit curve of experimental data in order to graphically determine the density of each metal Background: Understanding the relationship that exists between a substance’s mass and its volume. This relationship is expressed by the physical property called density. (D = M/V). In order to determine the volume of solids, a technique called water displacement is used. A fixed amount of water is added to a graduated cylinder and the volume of water is recorded.
The cross section helped to better understand the thickness, flow direction and distribution of the aquifer(s) within the mapping area. 3 river stream gages are placed in the stream in order to better understand the relationship between groundwater and surface water by giving quantities of discharge/recharge in cubic feet per second (cfs). Understanding the relationship between the groundwater and surface water gives aid for producing the potentiometric surface map which includes the gaining (effluent) and losing (influent) parts of the stream. Results Two aquifers were located, a confined and unconfined aquifer. The unconfined aquifer, or the upper aquifer, (see cross and contour map) consists of a predominately sand rich and partial gravel unit and is approximately 50 feet thick.
Add 0.1M HCl one drop at a time. Use the stirring stick and stir each time a drop has been added. Determine the pH after 5 drops have been added. Repeat the procedure until 30 drops have been added. 4.
Hydrate Lab The purpose of this lab is to analyze the percent water in a crystalline hydrate and to indentify the hydrate from a list of possible unknowns. The solid hydrate will be heated to remove the water, and the percent can be found by measuring the mass of the solid before and after heating. The hydrate will be indentified by comparing the percent water in the hydrate with the percent water calculated for the possible unknown. Before the lab there are pre-lab questions: 1. Describe the three general safety rules for working with a Bunsen burner.
* The final speed was recorded by the light gate detector about three times for each height. * To record the speed, we held the trolley at the top of the ramp with the help of meter rule. Then, as the trolley rolled down at the end of the ramp, the light gate detected its speed in metre per second(m/s). * The average speed of the final speed was calculated by : Vavg of the final speed (Vf) = V1+V2+V3 (m/s) 3 * The final speed was recorded by the light gate detector about three times for each
Water from a variety of sources that receive precipitation is being sampled. Using a pH meter, the pH of water samples is being measured. In the first approach using titration methods in combination with pH measurement, the volumes of sulfuric acid needed for reaching two different pH levels are being measured. Difference in the volume of sulfuric acid used, is an equivalent for the amount of CaCO3 expressed in grams per (gL-1) in the analyte. Therefore the alkalinity of water samples is being calculated.
Stoichiometry of a Precipitation Reaction Pre Lab Questions: (2Pts.) 1. What are the learning goals of this experiment? Predict the amount of product produced in a precipitation reaction, accurately measure the reactants and products of the reaction, determine the actual yield vs. theoretical yield, calculate the percent yield. 2.
Add water to your graduated cylinder until you have exactly 50ml (this is your volume). 3. Find the weight of the water plus the cylinder and record in your data table. 4. Find the weight of only the water by subtraction.
-We measured in each chemical and added water besides, HCl we added NaOH. Next, we measured the water temperature to begin with then added the substance to it to determine the finally temperature. We minus the initial and finally to decide if the reaction is exothermic and endothermic. 5. Describe the anticipated temperature change of a system in which an exothermic process is taking place.