Which is more difficult?

@SW-User you stole my answer sir. yes he should ask which is easier.

@SW-User but people who can't cook claim "they can't boil water" which means it's difficult to do :)

@SW-User Gordon Ramsey, on the equator with heavy water 😁

@JoeMW In that case it is easier to freeze. Heavy Water has a freezing point of 3.9 degrees C, while regular water freezes at 0 C. So heavy water doesn't need to be cooled as much.
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Boiling point of heavy water is 101.4 C and working under Gordan Ramsey's icy stare you are not getting there.

@SW-User yes

@JoeMW then my answer to you is yes also

@MartinTheFirst it's really amazing how much energy it takes to bring about a phase change for ice/water/steam

@JoeMW 44kJ for water to ice