1. A sample of tris(hyroxymethyl)aminomethane (H 2 NC(CH 2 OH) 3 ), which is a b

Question

1. A sample of tris(hyroxymethyl)aminomethane (H2NC(CH2OH)3), which is a base, with a mass of 0.4886 g is dissolved in water and used to standardize a solution of hydroiodic acid. An endpoint is reached when 27.59 mL of hydroiodic acid has been added. Determine the molarity (in mol/L) of the hydroiodic acid solution. Report your answer to four significant figures.


2. The standardized hydroiodic acid solution is then used to titrate 28.36 mL of a solution of sodium lactate (NaC2H5OCOO). An endpoint is reached when 21.33 mL of hydroiodic acid has been added. Determine the molarity (in mol/L) of the sodium lactate solution. Report your answer to four significant figures.

Explanation / Answer

Molecular weight of tris(hyroxymethyl)aminomethane is 121.14

therefore moles = mass / mol wt = 0.4886/121.14 = 0.00403 moles

volume of HI used = 27.59 mL

at equivalent point moles of tris(hyroxymethyl)aminomethane = moles of acid =  0.00403 moles

so moles of HI = 0.0051 moles

so molarity of HI = 0.00403 / 27.59 = 1.46 *10^-4 M

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.