Lecture : ISS REFLECTION

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rescuerory02

17 Jan 2023

School

John Abbott College

Department

Chemistry

Course

202-NYA-05

Professor

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Document Summary

After submitting my final research paper, i can say that i am overall proud of my work. I was really satisfied to see all the progress that has been made in my field of interest which was criminology. I felt very good about the quality of sources that i was able to find and found many common themes amongst their research. I was slightly disappointed with the selection/ quantity of sources, as it was difficult to find research on my specific topic. I wouldn"t say that the work was less demanding than i expected, however, it was much more enjoyable than i anticipated as i found my topic rather engaging. I was also able to refer back to some classes that i had taken when i was reading articles for my research as criminology combines may aspects of sociological studies such as psychology, Sociology and law, all classes that i have taken during my time in cegep.

Related Questions

The topic is Manganese

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A researcher was attemping to quantify the amount of DDT (dichlorodiphenyltrichloroethane) in spinach using gas chromotography mass spectrometry (GCMS). First attempts using external calibration proved diffucult, as reproducibilty and external standard agreement were poor. To overcome these problems, the researcher used the internal standard calibration method with chloroform as the internal standard.

To begin, the researcher examined a sample containing 5.96 mg/L DDT standard and 1.15 mg/L chloroform as the internal standard, producing peak areas of 4759 and 9405, respectively.

A) Using the above information, determine the response factor (F).

After establishing the response factor of the instrument, the researcher collected 8.55 g of spinach, homogenized the sample, and extracted the DDT using an established method (assume 100% extraction), producing a 3.47 mL volume of unknown sample. The researcher then prepared a sample that contained 0.500 mL of the unknown sample and 1.75 mL of 12.20 mg/L chloroform, which was diluted to a final volume of 25.00 mL. The sample was analzed using GCMS, producing peak areas of 6329 and 13127 for the unknown and chloroform, respectively.

B) Calculate the DDT concentration in the spinach sample. Express the final answer as milligrams DDT per gram of spinach.

Chemistry G/T Checkpoint 1: Unit 3

Predicting Pigmented Products

Background

Later in this unit, you will complete a lab to make pigments that can be used to add color to paint. pigments will be the colorful precipitate created with double replacement reactions. The pigment will be the precipitate, the solid is produced from the reaction of two aqueous solutions. We can predict precipitate formation using solubility rules.

The created pigments contain ions of transition metals, metals located in the center block on the periodic table. These metals have partially filled d-orbitals, resulting in characteristic colors. Since many of the transition metals have multiple oxidation states (charges), different ions of the same element have their own characteristic color. The unique properties of transition metals allow manufacturers to use them as the pigments in paints.

These colorful precipitates will be used to create paint by combining the precipitate pigment with a binder and an extender. Before the end of the unit, your group will create a plan to formulate a certain colored pigment for a piece of public art.

Analysis

For each of the four chemical reactions:

1. Predict the products for the following reactions that you will be conducting.

2. Balance each reaction using coefficients.

3. Use the solubility rules to determine the solid precipitate formed in each reaction. Use (s) to indicate a solid; circle the formula of the precipitate.