An ideal gas undergoes isothermal expansion at constant pressure. During the process :

What quantity (in mL) of a 45% acid solution of a mono-protic strong acid must be mixed with a 20% solution of the same acid to produce 800 mL of a 29.875% acid solution ?

A compound of molecular formula C₈H₈O₂ reacts with acetophenone to form a single cross-aldol product in the presence of base. The same compound on reaction with conc. NaOH forms benzyl alcohol as one of the products. The structure of the compound is :

Which of the following compounds is most reactive to an aqueous solution of sodium carbonate ?