no
Sugar and Salt
It is reversible. You can allow the water to evaporate, leaving the salt behind.
Mixing Alka-Seltzer and water is a reversible change because it can be undone by allowing the water to evaporate, leaving behind the original substances in their initial forms.
reversiublrt
Portland cement (and the concrete, mortar, thin set, or other masonry product made from it) doesn't dry. Rather, it cures by a chemical reaction initiated by putting water in it. The reaction is irreversible; hence, adding water to cement is an irreversible change.
This is a reversible process.
reversible?
No it is always reversible
reversible
No because you can't get the vinegar back to it's original state because some of the bacteria has gone inside the milk
No it isn't. Now I'm not an expert but to make it less watery by adding more flour.
The process of coffee cooling down and giving up heat to the environment is irreversible since the available heat in the environment will never re-heat the coffee. I believe the process of mixing coffee grinds with hot water is also irreversible. Theoretically it would be possible but i think you would have to do work on the system to separate the two which would make it irreversible.