Is there anyway somebody can pick a certain acid from the table and show me exam

Question

Is there anyway somebody can pick a certain acid from the table and show me example calculations for the third picture (both table and calculations underneath). Its a lab practical and I know being able to see the calculations, I'll be able to use it to study better and hopefully come up with a better grade. I couldn't thank you enough! Period #2: Lab Practical Exam: Identifying an unknown acid Each group member will be given a liquid sample of a pure acid with a given glL. The students will work independently to determine the equivalent weight oftheir acid. The equivalent weight of an acid is the mass of that acid that neutralizes 1 mole of NaoH. n additional way to think of equivalent weight is that the equivalent weight is the mass of acid titrated divided by the moles of NaoH required to reach the equivalence point. The possible acids are shown in the table below. The equivalent weights range from 46 g/mol to 212 g/mol. Name EW (g/mol) Formic acid Malonic acid 52 Maleic acid Citric acid Adipic acid 3,3-dimethylglutaric acid 80 112 a-furoic acid 122 Benzoic acid 138 Salicylic acid trans-cinnamic acid 148 p-Anisic acid 152 2-chlorobenzoic acid 157 1-naphthoic acid 172 3-nitrophenylacetic acid 181 4-chlorophenoxyacetic acid 187 2,5-dichlorobenzoic acid 3,5-dinitrobenzoic acid 212

Explanation / Answer

In general,
volume of the acid titrated = 25 mL = 0.025 L (according to the experiment)
Mass of the acid titrated (g) = volume of the acid titrated in L * given g/L
Note down the initial and final buret volume while titrating acid with base, (NaOH is in buret)
titrant volume delivered ( convert mL to L) = final buret volume - initial buret volume
mole eq of NaOH added = Volume of NaOH used in L * Normality of NaOH, mole eq / L
Normality of NaOH = Molarity of NaOH (given) * number of hydroxide ions in the base
   [ number of OH- ions in NaOH = 1 ]
At equivalence point that is when you observe pink color during observation,
moles eq of NaOH added = moles of acid present
Find the normality of acid using below equation,
volume of NaOH added * normality of base = 0.025L * normality of the unknown acid
normality of the unknown acid = moles of acid present / Equivalent weight of acid
Equivalent weight of the unknown acid =  moles of acid present / normality of the unknown acid

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