Chemistry Milk tastes sour when kept in the open for sometime due to the formation of __________? Options:A. lactic acidB. citric acidC. acetic acidD. carbonic acidView AnswerA. lactic acid Continue Reading Previous: __________ is one of the allotropic modifications of carbon.Next: Water Gas is a mixture of two gases Hydrogen & Carbon monoxide, while separating Hydrogen gas by liquification process which one is liquefied first__?