Compare The Determination Of The Concentration Of Metal Ion In Solution And Dilute

To determine which ions are present in the two unknown solutions. This will be accomplished by mixing three known solutions with three testing solutions. You will use this information to determine which ions are present in the unknown solutions.

The Scientist’s topic is about electrolyte concentration in different types of drinks. The question the scientist is trying to answer is “Which drink has the highest lectrolyte concentration for replenishing more electrolytes during and after physical activity?”. The independent variable is the type of drink, the dependet variable is the conductance (measured in amps) and the control variable is water.

The ending result of this experiment confirms that as five test tubes are lined up with the varying level of absorbance, different results in the level of absorbance will appear as well, this is visible in above table. Thus, this is due to the varying amount of water in the solution. The blank sample had a 0.30 in its level of absorbance.

But the result met the expectation because the color of the solution was reached the end point by changing from red to blue. The primary errors may occur because of misreading the buret while measuring the volume of EDTA. Another error can affect the result of the experiment was that letting the volume of EDTA excess the ending point; so that the volume of EDTA was overapply that lead error. The last source of error was that our unknown sample had high percentage in mass of Mg2+, so that we need more than 50 ml of EDTA( which was the capability of the buret) to reach the end point. We had to refill the buret while measuring; and also the large volume of solution made the color harder to recognize the end point. That also led to error.

Figure 1. Results recorded from experiment. After every 15 seconds for four minutes, the absorbance was recorded.

Prepare the unknown anion solutions for the students to analyze from the four 0.2 M stock solutions of anions. Any combination of these four anions may be prepared. Using a graduated Beral-type pipet, add 2 mL of each ion selected to a 13 X 100 mm test tube. Add distilled water to give a total volume of 8 mL. Stopper the test tube. A matrix of combinations, similar to the cation unknowns, can be generated for the anions.

The concentration of the PNP increased with the increase in time for the given wavelength. The increase in the PNP concentration increases the absorbance of the solution. The

Through this investigation the wavelength was to be determined in which the salt solution absorbs the most light. This was necessary in order to figure the concentration needed to create a solution form scratch. Once the appropriate absorbance wavelength was chosen this granted the flexibilty to concoct a solution from scratch or form a dilution in respect to the appropriate concentration. Utilizing the Beer-Lambert Law to control the path length and the constant through this experiment using the Spec-20, allowed concentration to be used as the identifiable variable. A solution of .100 M of Nickel (2) Nitrate will be used to obtain measurements of absorbances and concentrations at varied wavelengths. These absorbances and concentrations are then used to generate a graph.

The main objective of this experiment is to carry out qualitative analysis to identify metal cations in unknown solution 1.

7.14E-04 6.84E-04 63.8 Example calculation: Test tube #1 [FeSCN2+]= .0001 M x 1.0x13-3 L x [1/(1.0x10-3 L + 5.0x10-3L+4.0x10-3L Example of absorbance from the spectrophotometer: Test tube #6 Ε=15391 L= 1cm The concentration of FeSCN2+ was discovered using Beer’s Law (A= εl[FeSCN2+] A= εl[FeSCN2+] .11nm= 15391x1cmx[FeSCN2 +]

The collection of excitation and emission spectra provided intensity values that were divided into the intensity of our first solution containing no chloride ions. Our peak wavelengths were consistent and close to the expected wavelengths of 350 nm and 450 nm for excitation and emission, respectively. Our average excitation and emission peak wavelengths were 347.0 (+/-) 1.6 nm and 448.8 (+/-) 2.4 nm, respectively. The peak intensities also decreased in a linear fashion, thus we trusted our spectra data and proceeded with creating the Stern-Volmer plot based on the emission intensities. The trend line from our data is y=250.792x+0.933 with an R2 value of 0.993. Three things are provided by this trend line. The line is a strong fit (R2 = 0.993), the quenching constant of 251

This laboratory exploration attempted to determine the LC50 of copper concentration and a mixture of copper, zinc, and manganese from the mine tailing leachate on Daphnia magna. Acute metal toxicity testing guidelines were followed and dose response curve was developed to determine these values. The LC50 of copper concentration was approximated to be 56 μg/L. The LC50 for the mine tailing leachate with the prevalence of Zn, Cu, and Mn metals was the dilution factor of 1:1.57. These values were compared to literature values. It was concluded that various environmental parameters, including pH and hardness have a great influence on metal toxicity.

The equation shows the absorbance is directly proportional to the concentration, so as the concentration of the iron cation decreases

For each sample, the concentration of the solution decreases at a slightly lower rate than the sample before it (sample 1 to sample 2 has the most significant drop in concentration, as compared to sample 4 to sample 5, which has the lowest drop). However, the absorption does not decrease at a rate proportional to that of the concentration. The absorption value that was received for sample 3 does not conform with the value that was obtained during sample 2, as it was much lower than had been anticipated. The value was projected to be around 1.65-1.66, but instead went down to 1.489. There was a familiar occurrence with the blue dye (Table 2), with the difference between sample 4 and sample 5 being considerably greater than that between sample 3 and sample 5 (this may possibly be due to the difference between sample 3 and sample 4 being noticeably smaller as compared to the other samples).

in sport , the problems involved is concentration like attention has a time span , it can be taught over