ORP sensor

Mr. Black is owner of a small pharmacy shop. He sells a lot of pharmacy products. In his portfolio, there is also a hydrogen peroxide solution sold as a disinfection. Sold solution should be of 3 % w/w. Nevertheless, Mr. Black is not sure, whether his supplier does not cheat and to earn more, he sells him hydrogen peroxide solution with much smaller concentration.

Can you help to Mr. Black and find the concentration of hydrogen peroxide solution from his pharmacy shop? Is the solution sold in his shop OK?

The wine is a product that consists of several components, most of which is water (91 %). Besides water, ethanol (9-14 %), residual sugar, dyes and tannins, there are present also acids. There are more acids, but the most represented is tartaric acid, then malic, citric and lactic acid.  The proportion of the acids’ amount is a reason of characteristic taste and bitterness of each wine. Low content of acid results in insipid taste of wine, so the determination of total acidity is an important controlled item.