Which of the reagent is used to convert $2-$butanone into propanoic acid?    

Aryl aldehyde, on oxidation gives _______.

When propionic acid is treated with aqueous sodium bicarbonate, ${\text{CO}}_{\text{2}}$ is liberated. The ${\text{C of CO}}_{\text{2}}$ comes from the _________. 

Which of the following is the correct order of the acidic strength ?

Which of the following carboxylic acids is the most reactive towards esterification?

The carboxylic acid which shows reducing property is _______.

What is the formula of acrolein?

The IUPAC name of lactic acid is ______.

An organic compound, ${\mathrm{C}}_{\mathrm{3}}{\mathrm{H}}_{\mathrm{6}}\mathrm{O}$ does not give a precipitate with $2,4$-dinitrophenylhydrazine reagent and does not react with metallic sodium. It could be_______.