Amines, RNH2, react with picric acid to form amine picrate which absorbs strongly at 328 nm (ε = 17.15 L/mol.cm). A mass of 0.1825 g of the amine is dissolved in water and diluted to 100 mL. If this solution exhibits an absorbance of 0.336 at 328 nm using a 1.00 cm cell, what is the molar mass of the amine?

The iodine contained in every one mL of the 0.010 M iodine solution in the buret will react with 1.76 mg of vitamin C. (In other words, every mL of iodine solution needed for the titration indicates the presence of 1.76 mg of vitamin C in the juice sample.) If your titration used 5.86 mL of iodine solution, what mass of vitamin C is in your fruit juice sample (in milligrams, mg)?

22 23 24 25 26 21 16 17 18 19 20 15 A chemistry student weighs out 0.321 g of citric acid (H,C,H,0,), a triprotic acid, into a 250. mL volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with 0.2000M NaOH solution. Calculate the volume of NaOH solution the student will need to add to reach the final equivalence point. Round your answer to 3 significant digits. Ar I mL x10 Submit Assignment Continue Terms of Use Privacy Center Accessibility 2022 McGraw Hill LLC. All Rights Reserved. Show A IMG-6095.jpg IMG-6096.jpg IMG-6097.jpg IMG-6098.jpg IMG-6099.jpg MacBook Air DII F12 F11 F9 F10 80 E7 F8 F6 F5 F4 esc F2 F3 F1 & @ # $ % 4 5 6 7 8 1 2 3 P Q W E R т tab * 21

A commercial vinegar was analyzed by titration to determine the percent acetic acid. Briefly, 10.00 mL of vinegar sample was diluted to 100. mL solution in volumetric flask. A 25.00 mL aliquot from the diluted vinegar required 25.55 mL of 0.1005 M NaOH to reach the phenolphthalein endpoint. Which is the correct equation between the analyte and titrant reaction?       CH3COOH + NaOH → NaCH3COO + H2O     2CH3COOH + NaOH → NaCH3COO + H2O     C20H14O4 + NaOH → NaC20H14O4  + H2O     CH3COOH + 2NaOH → NaCH3COO + H2O

A student prepares a dilute solution of sodium hydroxide, NaOH (aq), starting with 6 M sodium hydroxide. She then titrates a 1.372 g sample of KHP with the dilute sodium hydroxide solution, NaOH (aq), to a phenolphthalein end point. 1. If the titration required 21.84 mL of sodium hydroxide, NaOH (aq), calculate the molar concentration of the sodium hydroxide solution, NaOH (aq). (Remember that KHP is potassium hydrogen phthalate, KHC8H4O4, NOT potassium hydrogen phosphorus!) 2.The student uses the same sodium hydroxide to titrate 10.00 mL of vinegar to a phenolphthalein end point. If the titration required 27.48 mL of sodium hydroxide, NaOH (aq), calculate the molar concentration of acetic acid, HC2H3O2 (aq), in the vinegar. 3. Calculate the mass percent of acetic acid, HC2H3O2 (aq), in the vinegar using the molar concentration for acetic acid, HC2H3O2 (aq), determined in part b and assuming the density of the solution is 1.01 g/mL.

Calculate the mass (in mg) of BSA contained in a solution that is prepared by mixing 25. mL of a 1.0 mg/mL BSA solution, 25. mL of distilled water, and 2.4 mL of assay dye solution.

Caculate the volume (mL) of 1.0 M potassium carbonate (K₂CO₃) needed to prepare 5.0g of the COPPER pigment. This is where the balanced chemical equation come in. You should be able to relate the moles of pigment to the moles of K₂CO₃, and from that calculate the volume of 1.0 M K₂CO₃ solution needed.  Please report your value as XX.X mL (one deicmal point and no units).