Use the particle in a box model to estimate the energies of the first electronicallyexcited states of ethylene, butadiene and hexatriene. Use a table of bond lengths to estimate the length of the box

The following data was taken in a GC experiment: tr of air (non retained) = 33s, tr of benzene = 275s, tr of toluene = 342s. From the literature it is known that the partition coefficient of benzene for the stationary phase in your column and at your column temperature is 650. Calculate K for toluene.

1) calculate the concentration of maleic acid solution?given : 25.00 mL of maleic acid of unknown contration is diluted with 50.00 mL of water. It is used to titrate 49.72mL of 0.1 M NaOH solution.

2)calculate the concentration of the diluted and undiluted CH3COOH (aq) solution.
given: 25.00 mL of unknown acetic acid solution is diluted with 50.00 mL water. It is used to titrate 49.83 mL of 0.1 M NaOH solution

A compound with molecular mass = 292.16 g/mol was dissolved in a 5.000 mL volumetric flask. A 1.000 mL aliquot was withdrawn, placed in a 10.000 mL flask and diluted to volume. The apparent absorbance of the diluted solution at 340 nm was 0.827 in a 1.000 cm cuvette. To check for a possible stray light effect, this sample was diluted by exactly a factor of 2; the apparent absorbance was now 0.421. A reagent blank showed negligible absorbance. The (true) molar absorptivity at 340 nm = 2.130 x 104 M-1 cm-1.

a) Estimate the stray light in the spectrophotometer.

b) Calculate the concentration of the compound in the cuvette.

c) What mass of the compound was used to make the solution in the 5.000 mL flask?

1. Design your own environmental laboratory experiment based on ANY of the labs we completed during CE 4371. You will be graded based on:
   1. Developing your overarching experimental question/goal,
   2. How you appropriately select your experiments to answer your question, and
   3. Your thought process of what your outcome will likely be and why.

Please be sure to detail your sampling procedures, where your samples will be collected from, how you will analyze your data, and what data will be collected in your theoretical data sheet. You can expand upon our experiments in lab. For example, if you want to measure more than just Fe on the AA machine, you can select copper, arsenic, etc., as long as it is measurable on an AA machine.

is just theoretical. You do not actually have to perform the experiment. Therefor, it phosphorus is very interesting to you, and hypothetically you are interested in how much phosphorus run off the farm produces, you would write down the sample collection procedure and the phosphorus testing procedure

1. A 30 g piece of metal (160.9 g/mol) melts at 1,560°C and its enthalpy of fusion is 12.6 kJ/mol. Calculate the entropy of fusion (J/k) per mole of the metal.

2. The temperature of a 374 g piece of granite is increased from 38.4°C to 62.6°C. What is its change in entropy (J/K)? The specific heat capacity of granite is 0.790 J/g^.K.

a compound with molecular formula c8h6o2 has an intense signal at 1696 cm-1 in its ir spectrum and only two signals in its 1H NMR spectrum (singlets at 10.14ppm and 8.05ppm). Draw the structure of the compound.

Describe at least one analytical technique that you could use that is more sensitive than Raman spectroscopy, FTIR spectroscopy, and energy-dispersive X-ray spectroscopy (EDS) analyses, but that might be destructive in its analysis of the material. Describe the benefits and other limitations of this technique.

Explain why atomic absorption spectroscopy and ion chromatographic (IC) technique are used as complementary techniques for water analysis.

Explain the relationship between oxidation-reduction and voltaic cells. Your answer must include equations.

Cacodylic acid (dimethylarsinic acid, HAsO2(CH3)2) is a common buffer used in biology to prepare and fix biological samples. The pKa of cacodylic acid is 6.3.

Part A What is the pH of a buffer solution prepared by mixing 20.0 mL of 0.0700 molL−1NaOH with 20.0 mL of 0.170 molL−1 cacodylic acid? Express your answer using one decimal place. pH =

Part B What is the pH of the buffer solution in part A after 0.0002 moles of H3O+ was added to the mixture? Express your answer using one decimal place. pH =

The solvent for an organic reaction is prepared by mixing 50.0 of acetone () with 61.0 of ethyl acetate (). This mixture is stored at 25.0 . The vapor pressure and the densities for the two pure components at 25.0 are given in the following table. What is the vapor pressure of the stored mixture?

Draw the structure of protonated histidine and indicate (draw and name) all possible non bonding interactions with water. include H bonding, and Hydration Spheres