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What is the enthalpy of the phase transition ice to water with respect to a #20*g# mass of ice?

Answer 1

We interrogate the reaction............

We interrogate the phase transition............

#H_2O(s) +Deltastackrel("0" ""^@C)rarrH_2O(l)#

Since both the #"reactant"# and the #"product"# are conceived to be at the same temperatgure, we only need consider the enthalpy change of the phase transition, and we expect reasonably, that the process gives an #"endotherm"#, as we are breaking ice-ice bonds..........

And we gots a #20*g# mass of ice.......

#Delta_"phase transition"=20*gxx334*J*g^-1=+6680*J=6.68*kJ#

And this represents #6680*Jxx1/(4.184*J*"cal"^-1)=??"cal"#

And if we have a 2 molar quantity of ice, i.e. a #36*g# mass, we simply solve.......

#Delta_"phase transition"=36*gxx334*J*g^-1=+12024*J=12.0*kJ#

#~=2874*"cal"#........

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Answer 2

Peyton Adams

The enthalpy of the phase transition from ice to water is approximately 334 J/g. Therefore, for a 20 g mass of ice, the enthalpy change would be 6680 J.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.