A student is given 250.0 g of sodium lactate, NaC3 H5 O3, and a bottle of lactic acid marked "

step 1 Okay, so we're going to make a buffer solution here. So let's go ahead and start with the 250 gr

A student is given 250.0 g of sodium lactate, NaC3 H5 O3,...

A student is given $250.0 \mathrm{~g}$ of sodium lactate, $\mathrm{NaC}_{3} \mathrm{H}_{5} \mathrm{O}_{3}$, and a bottle of lactic acid marked " $73.0 \%$ by mass $\mathrm{HC}_{3} \mathrm{H}_{5} \mathrm{O}_{3}, d=1.20 \mathrm{~g} / \mathrm{mL}$." How many milliliters of $73.0 \%$ lactic acid should the student add to the sodium lactate to produce a buffer with a $\mathrm{pH}$ of $4.50 ?$

Labs

Want to see this concept in action?

NEW

Explore this concept interactively to see how it behaves as you change inputs.

View Labs

Key Concepts

Concentration Conversions

This concept deals with converting between different concentration units. It includes using mass percent and density to determine the actual mass or moles of a substance in a given volume, which is essential when working with solutions in preparation of buffers or calculating reagent quantities.

Stoichiometry and Molar Conversions

Stoichiometry involves the calculation of molecules, moles, and mass in chemical reactions. In buffer problems, converting grams to moles using molar masses is crucial to determine the quantities of the acid and its conjugate base present or needed.

Buffer Solution

A buffer solution is a mixture of a weak acid and its conjugate base that maintains a nearly constant pH when small amounts of acid or base are added. This property is essential in many chemical and biological systems where pH stability is crucial.

Henderson-Hasselbalch Equation

The Henderson–Hasselbalch equation is used to estimate the pH of a buffer solution. It relates the pH to the pKa of the weak acid and the ratio of the concentrations of the conjugate base to the acid (pH = pKa + log([A?]/[HA])). This relationship enables one to calculate the amounts of the acid and its conjugate base required to achieve a desired pH.

Transcript

Please give Ace some feedback