Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
In an estimation of caffeine from tea, using HPLC, the following results were obtained. A series of calibration standards, injected with a 10uL loop injector, gave the linear regression for the calibration line as S = 0.6352 c +0.3633, where c is the concentration in ppm of caffeine and S the area of caffeine signal.
A 5.0 gram sample of tea was extracted with 200 mL of boiling water for 2 minutes. Caffeine from 2.0 mL of the above tea, after solid phase extraction, was diluted to 50. mL with the mobile phase. 10uL of the sample extract upon injection gave an area for the caffeine peak of 12.0 units.
Calculate the amount (mg) of caffeine present in the 5 g tea.
Calculate Hrxn for the reaction below. Ca(s) + 1/2 O2(g) + CO2(g) CaCO3(s) You are given the following set of reactions. Ca(s) + 1/2 O2(g) CaO(s) H = -635.1 kJ CaCO3(s) CaO(s) + CO2(g) H = 178.3 kJ kJ
Consider a liquid with a vapor pressure of 200. torr at 20.0 oC and a vapor pressure of 400. torr at 50.0 oC. What is the closest value to the normal boiling point of this liquid. A. 357 oC B. 295 oC C. 22.0 oC D. 18.2 oC E. 83.8 oC
Compare the proposed reaction mechanism for the sodiumhypochlorite oxidation of cyclohexanol with that involved in thechromic acid oxidation. Do you notice any similarities?
Blood contains several substances that minimize changes in its acidity by reacting with either an acid or a base. One of these is the hydrogen phosphate ion, HPO42-.
A sample contained a mixture of CdS and ZnS. The amount of CdS was determined by reacting 5.903 g of the sample with an excess of HCl to release H2S from each compound
An experiment identical to the one you just preformed is done by another student.except the amperage is continuously increased while the sulfuric acid concentration is kept constant
A solution is prepared by dissolving 0.18 moles of acetic acid and 0.18 moles of ammonium chloride in enough water to make 1.0 L of solution. Find the concentration of ammonia in the solution.
You are to prepare 250 grams of 7.00% sodium carbonate solution. How many grams of sodium carbonate and how many mL of water do you use?
Use the equilibrium constants to calculate DeltaGo for the formation of [Cr(NH3)6]2+, [Cr(en)3]2+, and [Cr(dien)2]2+ from [Cr(H2O)6]2+ and NH3, en, or dien, respectively.
A solution contains 15mL 0.1 M KI, 15 mL of DI water and 5 mL o f3% H2O2. After the decomposition of H2O2 is complete, you titrate the solution with 0.1 M AgNO3. If the catalyst, I-, is not consumed in the reaction and is completely recovered, wha..
Can someone please help and draw out step by step mechanism for dehydration of 1-Methyl-1-cyclohexanol using phosphoric acid.
What is the enthalpy change for the combustion of 12.5 g C4H10 in excess oxygen? C4H10 g + 13/2 O2 g = 4 CO2 g + 5 H2O g H= -1895 kJ
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd