3. This is the standard procedure for determination of nicotine in urine. A 1.00mL sample was placed in a 12mL vial. 5-aminoquinoline was added as the internal standard (5 pg). The sample was monitored using mass spectrometry at m/z values for nicotine (84) and the internal standard (144). Given the following data determine the concentration of the two unknown samples Nicotine (ug/L) 12 Area Area 0.056 0.402 0.059 51 102 157 205 0.391 0.669 1.063 0.684 1.011 1.278 0.51 1.355 0.53 1.32 Unknown 1 Unknown 2 1.18

Is the chart correct?

A piece of Gold weighing 12,359 Kg is suspected of being contaminated with Iron. To perform an instrumental analysis and To confirm whether or not it contains Fe, a portion of the sample (0.954 g) is taken from the piece and dissolved with 25 mL of aqua regia. Heats up For its complete dissolution, it is cooled and made up to 100 mL. A 10 mL aliquot is taken from this solution and made up to 50 mL. From This last solution is given the appropriate treatment to visualize Fe+2, for which the 1,10-phenanthroline reagent is added. (it forms a complex that is red in color) and is taken to a visible spectrophotometer and with a 12 mm cell a absorbance of 0.45. Previously, a calibration curve of Fe+2 was obtained under the same instrumental conditions obtaining the following data: (view table) Calculate the purity of the gold piece, assuming impurities only due to Fe.

Consider Table 1, which lists the volumes of the Fe3+ and SCN- solutions used for the continuous variation method. Note that each of the stock solutions is 0.002 M before mixing. What are the initial concentrations of Fe3+ and SCN- for solution 4, where the volumes are both 5 mL? [Initial meaning after they are mixed, but before]they reach equilibrium)

A 100 ml bottle of metronidazole 100 mg/ml suspension is available in your pharmacy. Calculate the volume of this suspension needed to be diluted with cherry syrup to prepare 60 ml of a 4% metronidazole suspension. 1 ml of a 1:1000 epinephrine injection was mixed with 20 ml of 1% lidocaine injection. Calculate the new ratio strength of epinephrine in the admixture. (IGNORE ANY VOLUME CHANGES AFTER ADMIXTURE) Instead of preparing 4 grams of tetracaine hydrochloride 4% gel an 8% gel was compounded by mistake. How many grams of the 8% gel and gel base must be mixed to get 4 grams of a 4% gel? How many milliliters of 70% ethanol and 20% ethanol must be mixed to prepare 500 ml of 30% ethanol? A diphenhydramine elixir contains 12.5 mg drug in one teaspoon. The volume of oral vehicle that is to be added to 100 ml of this elixir to reduce its strength by one half its original strength is; 6.  90 capsules of Liothyronine (T3) 15 micrograms are to be prepared. The formula calls for a 1:10000…

Which statement is correct?   A) An internal standard is a different substance from the analyte.   B) An internal standard is the same substance as the analyte.   C) An internal standard is a same substance as the analyte matrix.

If the endpoints you reached during standardization of your NaOH solution were very precise (relative average deviation if 0.03%) but were all overshot (meaning too much NaOH was added an you passedyour equivalence point), is the reported molar concentration of the acid solution from this experiment greater than , less than or equal to the true concentration? Explain.

Calculate : 1)Mean Experimental solubility of calcium hydroxide 2)standard deviation 3)RSD(pph)

Following the monograph procedure, a 724-mg of aspirin (MW=180 g/mol) dissolved in 18.5 ml of cold neutralized alcohol. This solution was then initially titrated with 0.101 N sodium hydroxide solution, then later neutralized with 0.104 sulfuric acid. What is the percentage purity of the sample?   1. What is the milliequivalent weight consumed by the acidic titrant? a. 1.5392 g-meq b. 2.0907 g-meq c. 1.4948 g-meq d. 2.1528 g-meq   2. What is the milliequivalent weight consumed by the basic titrant? a. 5.8656 g-meq b. 1.5392 g-meq c. 5.6964 g-meq d. 1.4948 g-meq   3. What is the difference of milliequivalent weight consumed in the reaction? a. -4.1572 g-meq b. 4.3708 g-meq c. 0.5515 g-meq d. 4.1572 g-meq