Question

whole milk is mixture. when bacteria in the milk digest part of the m ixture, changes occur. lactic acid is produces, and the milk tastes sour. explain why this process is a chemical change.

Answer 1

because it cannot be changed back to milk.

Answer 2

because chemicals change oO

the process that happens here is: the glucose contained in milk gets digested into lactic acid. under the pH of milk, the lactic acid will give away a proton, resulting in the sour taste and milk clotting. glucose isn't as sour as lactic acid, this is your proof of chemical change. it "could" be converted back into milk, but no bacterium wants to do that unthankful job :-)

Answer 3

this process is called fermentation!

Answer 4

realy Schleifspur it happens becuase as far i knw we never studied or seen this thing happen can u tell me how it can be.. plz w8in.. for ans. :)

Answer 5

I didn't say that it happens. I said that theoratically, it's possible. and, in the next sentence, I postulated that it doesn't happen. ;-)