Please help with the highlighted figures. I need the answer but also the step by

Question

Please help with the highlighted figures. I need the answer but also the step by step formulas to understand it.

Experiment 5 Report Sheet Identifying a Weak Acid Concentration Analysis: 1.Molarity of the NaOH solution (M 2. Volume of NaOH Added at equivalence (mL [3] Millimoles NaOH added (mmol 4. Volume of initial weak acid solution (mL [5] Molarity of unknown Acid (M [6] Average Molarity of Acid (M) Trails #2 and #3 on! Identity Analysis 7. Volume of NaOH Added at equivalence (mL) (Same as 8. pH at 1/2 Equivalence point [9] Average pH at 1/2 Equivalence point #2 & #3 on! [10] Average Ka #2 and #3 on! [11] Unknown Acid (from Table) Based on trials 2 and3 Trial 1 (fast) Trial 2 (slow) Trial 3 (slow) 0.095 30.30 23.90 24.00 25.00 25.00 25.00 30.30 23.90 24.00 4.38 4.55 4.61 4.58 Ka Acid Citric Acid Chloroacetic acid Nitrous acid Acetic Acid arbonic acid Hypochlorous acid 0.07 0.00 0.00 0.00 0.00 0.00

Explanation / Answer

Trial 1: 30.30 ml of 0.095 M NaOH solution is added

No. of milimoles of NaOH = (volume×molarity) milimoles = 30.30×0.095 milimole = 2.88 milimoles

Molarity of unknowm acid = ( volume× molarity of NaOH)/ volume of acid = 2.88/25 M = 0.115M

Trial 2: milimoles of NaOH = 0.095×23.90 mmoles = 2.27 mmol

Molarity of unknown acid = 2.27/ 25 = 0.091 M

Trial 3: mmoles of NaOH = .095×24 mmol= 2.28 mmol

Molarity of unknown acid= 2.28/ 25 M = 0.0912M

Average molarity of acid ( from 2 and 3) = (0.091+0.0912)/2 = 0.0911 M

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