How this calculation works
A warm liquid and cold ice do not necessarily end at the arithmetic average of their temperatures. Energy can melt ice without raising temperature, and cold enough ice can freeze some water before equilibrium is reached.
Conserve enthalpy relative to liquid water at 0 °C; positive total gives liquid warming, intermediate negative total gives an ice/water mixture at 0 °CA worked example
One kilogram of twenty-degree water supplies 83.72 kJ above the liquid-zero reference. A tenth of a kilogram of zero-degree ice carries minus 33.355 kJ on that same reference. Their sum is positive, so all ice melts and the 1.1 kg final liquid warms to about 10.938 °C. Increasing ice to half a kilogram leaves some solid at zero instead of producing a negative liquid-water temperature.
Good to know
Insulated pure-water equilibrium with fixed properties only; no dissolved ingredients, vessel heat, pressure correction, supercooling or time prediction. The phase classification is conditional on those assumptions. It does not model a real beverage or certify food handling.
Reference: OpenStax — phase change and latent heat (opens in a new tab) ↗
What this calculation answers
A warm liquid and cold ice do not necessarily end at the arithmetic average of their temperatures. Energy can melt ice without raising temperature, and cold enough ice can freeze some water before equilibrium is reached.
This page classifies the final phase from conserved energy. It reports final liquid and solid masses instead of assuming all ice melts or that the final temperature must be above zero.
The Water freezing energy and time calculator removes heat with an externally supplied cooling rate. This mixture instead shares a fixed initial energy budget between water and ice.
Use the right input conventions
Enter pure water and ice only. Salt, sugar, alcohol and other dissolved substances can alter heat capacities and phase boundaries, so a drink recipe cannot automatically be represented by these water properties.
The container is assumed to exchange no heat and have no thermal mass. Initial liquid is at or above zero and initial ice at or below zero. Both masses must be positive.
Interpret the result
Energy is referenced to the entire mass as liquid water at zero degrees. Positive total energy permits all-liquid warming. A total between the all-liquid and all-solid zero-degree boundaries leaves a mixture at zero with a calculable ice fraction.
A negative net-ice-melt metric means some of the initial liquid froze. The model predicts equilibrium state, not the time needed to reach it; stirring, particle size and surface transfer are not included.
Work through the example
One kilogram of twenty-degree water supplies 83.72 kJ above the liquid-zero reference. A tenth of a kilogram of zero-degree ice carries minus 33.355 kJ on that same reference.
Their sum is positive, so all ice melts and the 1.1 kg final liquid warms to about 10.938 °C. Increasing ice to half a kilogram leaves some solid at zero instead of producing a negative liquid-water temperature.
Where the model stops
Insulated pure-water equilibrium with fixed properties only; no dissolved ingredients, vessel heat, pressure correction, supercooling or time prediction.
The phase classification is conditional on those assumptions. It does not model a real beverage or certify food handling.
A few questions, answered
Why can the final temperature stay at zero?
Available energy may change how much ice is present without finishing the phase change.
What does negative net melting mean?
The final ice mass exceeds the initial ice mass because some original liquid water froze.