Based on Liquid Chromatography, how can I changed if the capacity value and selectivity value and resolution value is not in the proper range?

The solvent used for A :Cyclohexane:chloroform (75:25) The solvent Used for B: Ethyl ether:acetone (70:30). how can I mix solvent would you try next and explain why based on the two sets of results? what have to do to confirm the identity of these spots?

How can I make up 100ml of a solution containing Compound A (solid, purity of 83.7%) at 90 ug/ml and compound B (liquid, density of 1.12 and purity of 90.5%) at 30 ug/mL for HPLC reference standard? Please write all the steps for making this solution. The solvent is 0.1M H2PO4 in 75% methanol.

8.7 Step-wise solution to a numerical problem related to a flocculation-based water treatment plant having a flow of 25 MGD. The plant is to employ alum coagulation, and pertinent data for the flocculation basin are as follows: detention time = 20 min, G = 35 sec^-1 (at 50 degrees Fahrenheit), GT = ...

Hardness in groundwater is due to the presence of metal ions, primarily Mg2+ and Ca2+. Hardness is generally reported as ppm CaCO3 or mmol/L Ca2+. To measure the water hardness, a sample of groundwater is titrated with EDTA, a chelating agent; in the presence of the indicator eriochrome black T, sy...

Question 1: Hardness in groundwater is due to the presence of metal ions, primarily Mg2+ and Ca2+. Hardness is generally reported as ppm CaCO3 or mmol/L Ca2+. To measure the water hardness, a sample of groundwater is titrated with EDTA, a chelating agent; in the presence of the indicator eriochrome...

Photorespiration is considered a wasteful process that decreases the growth of C3 plants. What experiment would you propose to minimize the role of photorespiration in plants and ideally see increased growth as a result? Provide a brief description of your experiment and how you could carry out the ...

The density of air at ordinary atmospheric pressure and 25 0C is 1.19 g/L. What is the mass of air, in kg, in a room that measures 12.5 ft by 15.5 ft by 8.0 ft? Please provide a detailed explanation.

The lethal inhalation dose of sarin for a 200 pound person has been determined to be 0.0015 mg. Determine the LD50 of sarin that researchers used to calculate this lethal inhalation dose.

Please show all work and steps to following: 11. In the welding shop of the XYZ Manufacturing plant you have a cylinder with a volume of 548L of a compressed gas, and the pressure gauge shows 238 psig at the room temperature 25 C. A welder was instructed to go outdoors to weld, and the temperat...

Describe the nature and characteristics of PCB's. Why are they of importance to an EH&S or FS professional who encounters them when coming upon an incident scene where they are present? What precautions, or actions, should the EH&S or FS professional take when faced with this situation? What happens...

Acetyl chloride is a colorless, fuming liquid used primarily in the chemical industry. a) How is acetyl chloride produced? If 915 gallons is produced and shipped, will DOT require the carrier to display the flammable placard? Explain your answer. b) When there is a bulk spill of this chemica...

Discuss the importance of economics as it relates to pollution prevention. Supple at least two seperate examples to augment your discussion.

What is ozone and how it works as a protective molecule for our environment? What are the effects of CFCs on the ozone layer? What other alternatives you can think of to diminish environmental impact of CFCs? Draw the electron dot structure of ozone, and explain its molecular shape and p...

I'm wondering if you could help me answer a few questions about a lab I'm doing. We are preparing an a,b-unsaturated ketone via Michael and aldol condensation reactions. The reactants are trans-chalcone and ethyl acetoacetate (in ethanol and NaOH). This creates 6-ethoxycarbonyl-3,5-diphenyl-2-cyc...

Please I answered all of them except b, therefore, I need help with answer b and also could you verify my answers please for a, c, and d? if they are wrong what would it be? Thank you -The pH of uncontaminated rain water is about 5.6. The pH of rain falling in Cleveland, OH is 4.2 and that in ...

Chemical dechlorination is a method for destroying PCB waste. How many kilograms of potassium ethoxide (KOEt, or KOC2H5) is needed to react with 500 kg of 2,3',4',5'-tetrachlorobiphenyl?

Can anyone explain to me the chemistry behind the fires that brought down the Twin Towers? Please provide links to your references.

1. A) Draw the Lewis structure of chlorine nitrate. b) Write out the chemical equations showing how chlorine nitrate is formed in the stratosphere and for the reactions that convert it back to active chlorine compounds. Include reactions that occur in polar stratospheric clouds. C...

'Resources' PowerPoint -Visually stunning, animated presentation explaining : 1. The Greenhouse Effect - how the sun's visible light is converted into trapped infra red light and heat, causing the planet to warm up. 2. The Ozone layer - what is Ozone? where is the Ozone layer? How does it prot...

1) Free radicals (see Problem 115) are also important in many environmentally significant reactions. For example, photochemical smog, which forms as a result of the action of sunlight on air pollutants, is formed in part by the following two steps. X NO2 NO O O O2 O3 UV light Ozone damages rubber pr...

Please review the occurrence and cycling of calcium in nature, along with its use. Analyze and evaluate the article as to it's contemporary relevance regarding the elements availability, health implications and environmental impact.

Why do suppliers of compressed oxygen warn their customers to refrain from lubricating the values, regulaters, gauges, and fittings associated with oxygen storage containers?

A certain pesticide is fatal to fish fingerlings at a level of 0.5 parts per million in water. A leaking metal can containing 9.0 kg of the pesticide was dumped into a stream with a flow of 10.0 Liters per second moving at 0.4 km/hr. The container leaks pesticide at a constant rate of 5.0 mg/sec. Fo...

Assume a wind turbine with a hub 50 meters above the ground, a rotor diameter of 60 meters and a wind-conversion efficiency of 25 percent. The turbine operates in an area with an average wind-power density of 700 watts/sq meter at 50 meters altitude. How much electricity (kwH) can the turbine genera...

We are asked to determine the reaction and final chemical structure of when a glucopyranose unit is reacted with ammonium hydroxide? CH2OH + NH4OH = ?? 1) What does the final reaction structure look like? 2) Would this be referred to as "cat-...

How many metric tons of 5%-S coal would be needed to yield the H2SO4 required to produce a 1.5-cm rainfall of pH 2.00 over an area of 100 square kilometers? Hint: Calculate volume of rain, mol H+, mass of S, mass of coal

The pH in a lake the size of 4.0 km X 7.0 km and an average depth of 100 m is found to be 4.5. Calculate the mass of calcium carbonate that must be added to the lake water in order to raise its pH to 6.0, assuming the reaction of H+ with CaCO3 gives CO2 here (answer in grams). Hint: Calculate vol...

The average pH of precipitation in rural areas is 6.10. Assuming that the pH is controlled by the carbonate system, i.e., no anthropogenic acid gases are present in the atmosphere, calculate the amount of calcium carbonate (mg) dissolved per liter of rainwater. pKa1=6.33, KCO2=3.388e-02 [Hint: pCO2...

Taking the mass of the atmosphere to be 4.2E15 metric tons, what mass of carbon must be burned in order to increase the average carbon dioxide level in the atmosphere by 140ppm by volume (in metric tons)? Hint: The average molar mass of air is 28.96 g/mol.