Why should curd and sour substances not be kept in brass and copper vessels?

Hint : We have studied that acids react with active metals and produce salt and hydrogen . We know that every compound or salt obtained by these reactions are not useful, sometimes they may be harmful. We got this information from chemistry that curd or yogurt contains lactic acid and sour substances for examples lemons contains citric acid which can follow the reaction of acid with metal .We know that ; Metal + Acid$ \to $ Salt + Hydrogen Step-By-Step answer: Lactic acid is an organic acid which contains $ - COOH$ group. Hence it is a weak acid due to the presence of the $ - COOH$ group. Lactic acid develops in cow milk because of breaking down of bacteria. Fresh milk does not contain lactic acid. Dairy products such as yogurt, cheese and condensed milk contain high levels of lactic acid. The sour taste of substances is because they contain acid such as vinegar contains acetic acid, tamarind and grapes contains tartaric acid, lemons and oranges contains citric acid etc. Hence when these acids react with metals they give salt and hydrogen. If these kinds of substances which possess acids are kept in copper containers or vessels they will react and produce salt and hydrogen and the vessel will be corroded. It can also produce harmful products that may spoil the food. Note: Copper metal is placed below hydrogen in the reactivity series which is a very small difference which can be overcome by the difference in the duration of contact, temperature and oxidative nature of acid...

Why should curd and sour substances not be kept in brass and copper vessels? all acids are sour in nature.curd,is made from milk which is slightly acidic in nature(as it contains lactic acid).we know that acids react easily with metals to give salt and hydrogen gas.when kept in copper or brass vessels,curd(and other acidic food items) reacts with copper and forms toxic compounds which may be unfit for human consumption,and may cause food poisoning.thus it is not advisable to keep curd and other acidic or sour food items in copper or brass vessels.

Explanation: Both the Curd and sour substances are acids. Acids react with metals to produce salt and hydrogen gas. When sour substances like curd are kept in brass or copper vessels , the lactic acid in curd reacts with the metals which leads to the corrosion of the vessels as well as the formation of harmful salts that cannot be consumed. So, if such substances are kept in brass and copper vessels, the acid will react and the container will be corroded. There by may spoil the food.

Curd and sour substances not be kept in brass or copper vessels: • Curd and sour substances are both acids. • Acids combine with metals to form salt and hydrogen gas. • When sour things, such as curd, are stored in brass or copper vessels, the lactic acid in the curd reacts with the metals, causing corrosion and the creation of toxic salts that cannot be digested. • If such compounds are stored in brass or copper vessels, the acid will react and corrode the container. • As a result, the food may be spoiled.