1. Determining the Molar Mass of the Acid • Given mass of acid: 0.120 g • Volume of NaOH solution at first • equivalence point: 12.5 mL Molarity of NaOH: 0.1 M Calculation of moles of NaOH: [ \text{Moles of NaOH} = \text{Molarity} \times \text{Volume} = 0.1, M \times 0.0125, L = 1.25 \times 10^{-3}, \text{mol} ] Moles of Acid: Since the acid is diprotic, the moles of acid will be half the moles of NaOH used: [ \text{Moles of Acid} = \frac{1.25 \times 10^{-3}, \text{mol}}{2} = 6.25 \times 10^{-4}, \text{mol} ] Molar Mass of the Acid: [ \text{Molar Mass} \frac{\text{Mass of Acid}} = {\text{Moles of Acid}} = \frac{0.120, \text{g}}{6.25 \times 10^{-4}, \text{mol}} = 192, \text{g/mol} ] 2. Determining (K_a1) and (K_a2) • ⚫ pH at the first half-equivalence point (pH 1st half): 2.91 ⚫ pH at the second half-equivalence point (pH 2nd half): 7.5 Since pKa = pH at half equivalence point: (K_{a1}): [pka_1 = 2.91 ] [ K_{a1} = 10^{-2.91} \approx 1.23 \times 10^{-3}] (K_{a2}): [ pKa_2 = 7.5 ] [ K_{a2} = = 10^{-7.5} \approx 3.16 \times 10^{-8} ]

1. Determining the Molar Mass of the Acid • Given mass of acid: 0.120 g • Volume of NaOH solution at first • equivalence point: 12.5 mL Molarity of NaOH: 0.1 M Calculation of moles of NaOH: [ \text{Moles of NaOH} = \text{Molarity} \times \text{Volume} = 0.1, M \times 0.0125, L = 1.25 \times 10^{-3}, \text{mol} ] Moles of Acid: Since the acid is diprotic, the moles of acid will be half the moles of NaOH used: [ \text{Moles of Acid} = \frac{1.25 \times 10^{-3}, \text{mol}}{2} = 6.25 \times 10^{-4}, \text{mol} ] Molar Mass of the Acid: [ \text{Molar Mass} \frac{\text{Mass of Acid}} = {\text{Moles of Acid}} = \frac{0.120, \text{g}}{6.25 \times 10^{-4}, \text{mol}} = 192, \text{g/mol} ] 2. Determining (K_a1) and (K_a2) • ⚫ pH at the first half-equivalence point (pH 1st half): 2.91 ⚫ pH at the second half-equivalence point (pH 2nd half): 7.5 Since pKa = pH at half equivalence point: (K_{a1}): [pka_1 = 2.91 ] [ K_{a1} = 10^{-2.91} \approx 1.23 \times 10^{-3}] (K_{a2}): [ pKa_2 = 7.5 ] [ K_{a2} = = 10^{-7.5} \approx 3.16 \times 10^{-8} ]

Introductory Chemistry For Today

8th Edition

ISBN:9781285644561

Author:Seager

Publisher:Seager

Chapter9: Acids, Bases, And Salts

Section: Chapter Questions

Problem 9.109E

See similar textbooks

Similar questions

. Which of the following will affect the total amount of solute that can dissolve in a given amount of solvent? a. The solution is stirred. b. The solute is ground to line particles before dissolving. c. The temperature changes.
Distinguish between the terms slightly soluble and weak. electrolyte.
A scientist has synthesized a diprotic organic acid, H2A, with a molar mass of 124.0 g/mol. The acid must be neutralized (forming the potassium salt) for an important experiment. Calculate the volume of 0.221 M KOH that is needed to neutralize 24.93 g of the acid, forming K2A.
In Exercise 12.49, what is the allowed concentration of AgCl in g per 100 g of water? The Safe Drinking Water Act of 1974 established the maximum permitted concentration of silver ion at 0.05 ppm. What is the concentration of Ag+ in parts per million in a saturated solution of AgCl? (NOTE: 1 ppm = 1 mgofsolute/L of solution.)
A solution of sodium cyanide, NaCN, has a pH of 12.10. How many grams of NaCN are in 425 mL of a solution with the same pH?
In a 4.9 mm aqueous solution of benzoic acid (C6H₂CO₂H), what is the percentage of benzoic acid that is dissociated? You can find some data that is useful for solving this problem in the ALEKS Data resource. O Round your answer to 2 significant digits. []% x10 X Ś |||
. Calculate the moles of H+ delivered to eachsample based on your experimental dataand record these values in Data Table 2. 0.1M HCl = 0.1 moles HCl / 1 Liter solutionCalculate the moles of OH- in each sampleand record these values in Data Table 2. H+ + OH- H2O Calculate the moles of Ca2+ in each sampleand record these values in Data Table 2. Ca(OH)2 Ca2+ + 2OH24. Calculate the molar solubility of Ca(OH)2for each sample and record these values inData Table 1. Molar solubility = moles / Liter Sample 1 Sample 2 Sample 3 Mass of Erlenmeyer Flask 25.37 25.37 25.37 Mass of Erlenmeyer Flask + Calcium Hydroxide Solution (lime water) 28.18 28.21 28.28 Mass of Calcium Hydroxide Solution Volume of Ca(OH)2 Density = 1.000 g/mL Concentration of HCl (M) Initial HCl volume in Syringe 1.0ml 1.0ml 1.0ml Final HCl volume in Syringe .54ml .58ml .5ml Volume of HCl Delivered .46ml .42ml…
someone answered my question in the bartleby, but I can't understand the steps and answers. I need someone who can translate the steps and answer more clealy without the computer commands.
I dont know how to do this question
In no morethan 1000 words. Propose a procedure in preparing a 500 mL 1 M sodium hydroxide solution using the following materials, reagents, glass wares, and instruments. (Show necessary calculations): Materials/Glass wares:• 500 mL beaker• 500 mL volumetric flask• Weigh boat Reagents:• Distilled water• 300 g NaOH pellets Instruments:• Analytical balance.
It requires 10.75 mL of 1.05 M Ba(OH)2 to neutralize (titrate) a 35.00 mL sample of HX. What is the concentration of HX solution (measured in moles per liter)? Report to 3 significant figures.
3. Calculate the volume of H,SO, with T(H,SO, NaOH) = 0.003025 g/ml what is required to react with 20,00 mL 0,1065 N solution of NaOH. Be sure to write down: 1) what analysis results are given; 2) write the corresponding reactions equations; 3) the mathematical expression of the law of equivalents and use it in solving the problem; 4) perform all calculations with comments; 5) make conclusion.