Lab 2

Name the following Fe(NO3)2

The spectroscopic data given in the table was generated for two different concentrations of a solution. Concentration (M) Absorbance 0.0141 0.1391 0.1445 0.6015 What is the slope of the line formed by these points? m = 3.545 What is the y-intercept? b = 0.0893 What is the concentration of a solution with an absorbance of 0.333 ? concentration: Incorrect M

pour it 2. Still sleepy from a late night studying, you take the milk out of the refrigerator and pour it on your lemon juice to milk to make paneer (fresh cheese). As a group, craft a chemical explanation for the fact of coagulated milk onto your cereal. The last time you saw milk coagulate like that was when you added breakfast cereal. Unfortunately, by the time you notice the funny smell you have already poured clumps lemon juice to milk to make paneer (fresh cheese). As a group, craft a chemical explanation foea added that spoiled milk coagulates.

Assume that vinegar is 5% acetic acid (by mass) at a density of 1.01 g mL-1.  This means that 100 mL of vinegar you would have 5.05 g of acetic acid.  Calculate the molar amounts of acetic acid and sodium bicarbonate that you will use in this experiment.

What are replicates in Analytical Chemistry? O The component of a sample that repeats over different assays. Similar assays done to different samples A sample that contains exactly the same amount of analytes than the original sample similar samples that are analyzed at the same time and in the same way

Historically, toxicology testing has been focused on one chemical at a time, yet we are rarely expose to chemicals in isolation. Why do you think this approach to testing has been taken? What challenges may be involved in studying mixtures of chemicals?

A1

Answer part e. of this chemistry experiment question

3. A student obtains a liquid sample of green food coloring that is known to contain a mixture of two solid pigments, one blue and one yellow, dissolved in an aqueous solution of ethanol. Which of the following setups is most appropriate for the student to use in order to separate and collect a substantial sample of each of the two pigments? In A. D. bab

IMAGINE YOU ARE DOING THE EXPERIMENT AND ANSWER THE QUESTIONS GIVEN.

Complete the table by entering the molarity of B2- for each standard solution. Show an illustrative calculation for tube ‘A’. Use the dilution formula and express each result to one more digit than allowed by applying the rules of significant figures. Standard Volume of stock B2- solution taken, mL Molarity of dilute B2 Construct a graph of Absorbance vs. molarity of B2- in Excel using the data in the preceding table. Make certain to title the graph and include axes labels with proper units. Absorbance is dimensionless (has no unit). Add a linear trendline to the graph but do not set the y-intercept to zero Solid M2B is added to 25 mL of water, the resulting mixture is continually stirred for 1 hour. At this point, it is assumed that equilibrium (eqn 3) has been established. The mixture is transferred to a test tube, and the test tube is centrifuged to assure that any residual solid M2B is fully settled out. A portion of the supernatant in the test tube is carefully…

After adding 50 mL of NaOH solution, but he sample in the flask still had not turned pink. What error did the student make?

Pictured are the two antacids used in this experiment. Note the information about tablets per dose, tablets per container, and cost per container written on the jars. You can determine the volume of HCl neutralized per dose of antacid using the following formula: In the Brand X titration, the mass of antacid sample was 0.486 g. When titrated, a total volume of 16.67 mL HCl was used. What was the volume of HCl neutralized per dose of Brand X? Do not include a unit with your answer. TUMS antacid: 2 tablets / 500 mg dose 50 tablets / container Cost: $4.98 / container Brand X antacid: 2 tablets / 500 mg dose 40 tablets / container Cost: $3.75 / container

A student performed the identical experiment to isolate Fe, NaCl, and SiO2 in a mixture. They performed every step correctly except they extracted with 10 mL of deionized water only once rather than the recommended four times.  a.) Will this error make the calculated mass percent of Fe, NaCl, and SiO2 accurate or inaccurate. Explain your answer. b.) Will the calculated mass percents of Fe, NaCl, and SiO2 be higher or lower than the true values? - Mass percent of Fe (HIGHER or LOWER) Must explain answer. - Mass percent of NaCl (HIGHER or LOWER) Must explain answer. - Mass percent of SiO2 (HIGHER or LOWER) Must explain answer.

Dr. Evil prescribed Austin 2.0 mL of 1:40 evil truth serum. However, Scotty ordered 1:100 evil truth serum. What volume (mL) of 1:100 evil truth serum does No. 1 have to inject in Austin to achieve the prescribed dose?

Please anwer question and exlpain why