Acid base test Acidity test: Na 2 CO 3 solution(conc) + acid → warm → effervescent Strong effervescent that means acid. Weak effervescent that means acidic. Conc. Hcl test: when substance soluble in 10% NaOH that means acid.if add HcL in same test tube → reprecipted again
Conc. HCLAcidity testL.PH2Oacids Reppt.effervescent Change blue to red MiscibleFormic Acetic Change blue to red solubletartaric citric Not done Insoluble in H2O,dil HCL but soluble in 10%NaOH benzoic phthalic salicylic All strong acid
Preliminary test Soda lime test: Formic and acetic acid: not done for solid only. Tartaric and citric acid: burnt sugar odor on hot. Benzoic and phthalic acid: benzene odor on hot. Salicylic acid: phenolic odor on hot.
Differentiation tests Acetic acidFormic acid - Turbidity or whit ppt. (Hg2CL2) HgCL2: HgCL2+acid (wait 5 min) - Disappear violet color, form brown ppt. (manganus oxide Alkaline Kmno4: acid + Na2CO3 sol. +KMNO4 Fruity or ripe apple odor - Esterfication : ethOH +acid + Conc. H2SO4 heat then pour it onto H2O
Citric acidTartaric acid Eff. And yellow stainEff. And charringConc. H2SO4: (hot) Discoloration of violet color anf form white ppt. -Denges: acid+ H2O+ denges reagent boiling (without cooling) + KMNO4 Phthalic acidBenzoic acid Unstable pink color-Phthaline test: Phenol+ acid +Conc. H2SO4 heat then pour it onto 10% NaOH Reddish brown color give green flourescence if dilute it with water -Flourescence; Acid + resercinol+ Conc. H2SO4 heat then pour it onto 10% NaOH
Salicylic acid Esterfication: methanol+ saliucylic acid+ Conc H2SO4heat then pour it onto 10 ml of H2O → vicks odor of winter green oil due to methyl salicylate formation. Formaldehyde: Formaldehyde+ salicylic acid + Conc. H2SO4 → crimson red color on the wall. Phthaline test: Salicylic acid + phthalic unhydride +Conc. H2SO4 heat then pour it onto 10 ml of 10% NaOH → unstable pink color
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