Titration of a 0.492-g KH₂PO4 used 25.6 mL of 0.112M NaOH. What is the percent purity of KH₂PO4? MW KH₂PO4 = 136.1 g/mol H₂PO4¹ + OH¹ HPO4² + H₂O

You are running an acid-base titration with hydrochloric acid and calcium hydroxide.  The calcium hydroxide is your titrant; it has a known concentration of 0.0891 M.  You have added 25.0 mL of the hydrochloric acid solution to an Erlenmeyer flask along with 2 drops of phenolphthalein (fee’-nol-thay-leen) indicator.  To begin your first trial, you fill a clean 50 mL buret with the calcium hydroxide solution.  Your starting volume is 0.25 mL. After the addition of solution from the buret, you see a color change in the flask, and the end point of the reaction is reached.  You note the final volume in the buret to be 18.75 mL. You begin again for your second titration trial.  You add 24.8 mL of the hydrochloric acid solution to a clean flask along with 2 drops of indicator.  You refill the buret to an initial volume of 1.42 mL.  When the reaction is complete, you note the final volume in the buret at 16.74 mL. Then you complete a third trial.  You add 25.6 mL of hydrochloric acid solution…

A chemistry graduate student is given 125. mL of a 1.20M dimethylamine ((CH3)₂NH) solution. Dimethylamine is a weak base with K₁=5.4 × 10-4. What mass of (CH3)NH₂Br should the student dissolve in the (CH3) NH solution to turn it into a buffer with 2 pH = 11.05? You may assume that the volume of the solution doesn't change when the (CH3)NH₂Br is dissolved in it. Be sure your answer has a 2 unit symbol, and round it to 2 significant digits.

7.7 g of citric acid (MM = 192.1 g/mol) can be titrated with NaOH according to the following balanced chemical equation.           H3C6H5O7  (aq) + NaOH(aq) → H2O(l) + Na H2C6H5O7(aq) what would the curve for the titration of the neutralization of the three hydrogens of this acid with NaOH look like?

A 25.00 mL sample of 0.1500 M lactic acid was added to a beaker. It was titrated with a 0.1700 M of NaOH in a burette. K₂ =1.4x104 of lactic acid. Calculate the pH when 8.00 mL of NaOH is added in the titration.

A can of Coke contains 12 fluid ounces, which is approximately 355 mL. You transfer 50.00 mL of the Coke into a conical flask, then titrate the sample with 0.01000M NaOH. It requires 8.62 mL to reach the first equivalence point of the titration of H3PO4. How many milligrams of phosphoric acid are in the can? (MW phosphoric acid = 97.994 g)

Calculate the molarity of an NaOH solution from the following titration data.  Be sure the answer has the correct amount of significant figures.  The chemical equation for this titration is as follows: NaOH  +  KHP  ⟶  NaKP  +  H2O NaOH buret reading, inital:  15.27 mL NaOH buret reading, final:     8.32 mL Mass of KHP (204.22 g/mol):  1.1592 g Calculate the molarity of an NaOH solution from the following titration data.  Be sure the answer has the correct amount of significant figures.  The chemical equation for this titration is as follows: NaOH  +  KHP  ⟶  NaKP  +  H2O NaOH buret reading, inital:  15.27 mL NaOH buret reading, final:     8.32 mL Mass of KHP (204.22 g/mol):  1.1592 g

What is the pH of a buffer solution if you have 250 ml of a 1.56M Acetic Acid and you added 26.56 grams of sodium acetate (NaCH3CO2)? What is the new pH if you now add 1gram of NaOH to the buffer solution?

(a) Lactic acid, (CH3CH(OH)COOH) is a common biomolecule which can accumulate in muscles during intense exercise. A chemist prepares a buffer using 225 mL of 85 M lactic acid (Ka = 1.38 x 10-4) and 435 mL of 0.68 M sodium lactate. What is the pH of the buffer?             What is the pH of the lactate buffer if 0.25 moles of gaseous HCl is added?

In the titration of 25.00 mL of a water sample, it took 19.040 mL of 4.965x 10−3 M EDTA solution to reach the endpoint.   The total hardness is always listed in parts-per-million (ppm) of CaCO3 (or mg CaCO3 / Kg H2O). Since the density of water is 1.0 g/mL, one ppm would be the same as the number of mg of CaCO3 per liter of water. Determine the number of moles of CaCO3 present in the titrated sample of water, assuming that all the Ca2+ combines with CO32−. (enter your answer with 3 significant figures)