Traditional Culture Encyclopedia - Traditional festivals - One step in the traditional production process of "aged vinegar" is called ... (chemistry).

One step in the traditional production process of "aged vinegar" is called ... (chemistry).

As can be seen from question B, improving the quality of vinegar means removing water and retaining acetic acid, among which acetic acid remains unchanged. The obtained superior vinegar contains 500×5 acetic acid. 4% = 27g, the amount of acetic acid is unchanged, and the acetic acid in semi-finished vinegar is still 27g, and 27/3% = 900g, which is the quality of semi-finished vinegar. Then the amount of water removed is 900-500 = 400g, and B is selected.