Q34 of 58 Page 1

What do you observe when you drop a few drops of acetic acid to a test tube containing:

(i) phenolphthalein


(ii) distilled water


(iii) universal indicator


(iv) sodium hydrogen carbonate powder

Acetic acid is a weak acid, following changes are observed --


 


(i) Phenolphthaleinno change/remains colorless


 


(ii) Distilled water acetic acid dissolves in distilled water.


 


(iii) Universal indicator turns orange


 


(iv) When added to Sodium hydrogen carbonate powder evolution of colorless, odorless gas (carbon dioxide) with brisk effervescence takes place.


 


CH3COOH(aq) + NaHCO3 → CH3COOHNa (aq) +H2O(l) + CO2(gas)


 

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